#!/usr/bin/env node

/**
 * GSD Tools — CLI utility for GSD workflow operations.
 *
 * Replaces repetitive inline bash patterns across ~50 GSD command/workflow/agent files.
 * Centralizes: config parsing, model resolution, phase lookup, git commits, summary verification.
 *
 * Usage: node gsd-tools.cjs <command> [args] [--raw] [--pick <field>]
 *
 * Atomic Commands:
 *   state load                         Load project config + state
 *   state json                         Output STATE.md frontmatter as JSON
 *   state update <field> <value>       Update a STATE.md field
 *   state get [section]                Get STATE.md content or section
 *   state patch --field val ...        Batch update STATE.md fields
 *   state begin-phase --phase N --name S --plans C  Update STATE.md for new phase start
 *   state signal-waiting --type T --question Q --options "A|B" --phase P  Write WAITING.json signal
 *   state signal-resume                Remove WAITING.json signal
 *   resolve-model <agent-type>         Get model for agent based on profile
 *   find-phase <phase>                 Find phase directory by number
 *   commit <message> [--files f1 f2] [--no-verify]   Commit planning docs
 *   commit-to-subrepo <msg> --files f1 f2  Route commits to sub-repos
 *   verify-summary <path>              Verify a SUMMARY.md file
 *   generate-slug <text>               Convert text to URL-safe slug
 *   current-timestamp [format]         Get timestamp (full|date|filename)
 *   list-todos [area]                  Count and enumerate pending todos
 *   verify-path-exists <path>          Check file/directory existence
 *   config-ensure-section              Initialize .planning/config.json
 *   history-digest                     Aggregate all SUMMARY.md data
 *   summary-extract <path> [--fields]  Extract structured data from SUMMARY.md
 *   state-snapshot                     Structured parse of STATE.md
 *   phase-plan-index <phase>           Index plans with waves and status
 *   websearch <query>                  Search web via Brave API (if configured)
 *     [--limit N] [--freshness day|week|month]
 *
 * Phase Operations:
 *   phase next-decimal <phase>         Calculate next decimal phase number
 *   phase add <description> [--id ID]   Append new phase to roadmap + create dir
 *   phase insert <after> <description> Insert decimal phase after existing
 *   phase remove <phase> [--force]     Remove phase, renumber all subsequent
 *   phase complete <phase>             Mark phase done, update state + roadmap
 *
 * Roadmap Operations:
 *   roadmap get-phase <phase>          Extract phase section from ROADMAP.md
 *   roadmap analyze                    Full roadmap parse with disk status
 *   roadmap update-plan-progress <N>   Update progress table row from disk (PLAN vs SUMMARY counts)
 *   roadmap annotate-dependencies <N>  Add wave dependency notes + cross-cutting constraints to ROADMAP.md
 *   roadmap validate                   Validate phase ID convention compliance
 *   roadmap upgrade [--apply] --convention milestone-prefixed  Migrate phase IDs to M-NN convention
 *
 * Requirements Operations:
 *   requirements mark-complete <ids>   Mark requirement IDs as complete in REQUIREMENTS.md
 *                                      Accepts: REQ-01,REQ-02 or REQ-01 REQ-02 or [REQ-01, REQ-02]
 *
 * Milestone Operations:
 *   milestone complete <version>       Archive milestone, create MILESTONES.md
 *     [--name <name>]
 *     [--archive-phases]               Move phase dirs to milestones/vX.Y-phases/
 *
 * User Story Validation:
 *   user-story validate --story "..."  Validate "As a / I want to / so that" format
 *                                      Returns JSON { valid, errors[], slots: {role,capability,outcome} | null }
 *                                      --pick valid  Emit bare boolean (for workflow boolean checks)
 *
 * Drift Guard (ADR-22):
 *   drift-guard authority                Resolve effective source-grounding authority
 *                                        (reads plan_review.source_grounding_authority + intel.enabled from config)
 *   drift-guard severity --status <S>    Classify a symbol verdict into { severity, hardBlock }
 *     [--authority <A>]                  Status: VERIFIED|MISSING|AMBIGUOUS|UNCHECKABLE
 *                                        Authority: grep|intel|treesitter|lsp|scip (default: config-resolved)
 *
 * Validation:
 *   validate consistency               Check phase numbering, disk/roadmap sync
 *   validate health [--repair]         Check .planning/ integrity, optionally repair
 *   validate agents                    Check GSD agent installation status
 *
 * Progress:
 *   progress [json|table|bar]          Render progress in various formats
 *
 * Todos:
 *   todo complete <filename>           Move todo from pending to completed
 *
 * UAT Audit:
 *   audit-uat                           Scan all phases for unresolved UAT/verification items
 *   uat render-checkpoint --file <path> Render the current UAT checkpoint block
 *
 * Open Artifact Audit:
 *   audit-open [--json]                 Scan all .planning/ artifact types for unresolved items
 *
 * Intel:
 *   intel query <term>             Query intel files for a term
 *   intel status                   Show intel file freshness
 *   intel update                   Trigger intel refresh (returns agent spawn hint)
 *   intel diff                     Show changed intel entries since last snapshot
 *   intel snapshot                 Save current intel state as diff baseline
 *   intel patch-meta <file>        Update _meta.updated_at in an intel file
 *   intel validate                 Validate intel file structure
 *   intel extract-exports <file>   Extract exported symbols from a source file
 *   intel api-surface               Render api-map.json into API-SURFACE.md
 *
 * Scaffolding:
 *   scaffold context --phase <N>       Create CONTEXT.md template
 *   scaffold uat --phase <N>           Create UAT.md template
 *   scaffold verification --phase <N>  Create VERIFICATION.md template
 *   scaffold phase-dir --phase <N>     Create phase directory
 *     --name <name>
 *
 * Frontmatter CRUD:
 *   frontmatter get <file> [--field k] Extract frontmatter as JSON
 *   frontmatter set <file> --field k   Update single frontmatter field
 *     --value jsonVal
 *   frontmatter merge <file>           Merge JSON into frontmatter
 *     --data '{json}'
 *   frontmatter validate <file>        Validate required fields
 *     --schema plan|summary|verification
 *
 * Verification Suite:
 *   verify plan-structure <file>       Check PLAN.md structure + tasks
 *   verify phase-completeness <phase>  Check all plans have summaries
 *   verify references <file>           Check @-refs + paths resolve
 *   verify commits <h1> [h2] ...      Batch verify commit hashes
 *   verify artifacts <plan-file>       Check must_haves.artifacts
 *   verify key-links <plan-file>       Check must_haves.key_links
 *   verify schema-drift <phase> [--skip]  Detect schema file changes without push
 *   verify codebase-drift                Detect structural drift since last codebase map (#2003)
 *
 * Template Fill:
 *   template fill summary --phase N    Create pre-filled SUMMARY.md
 *     [--plan M] [--name "..."]
 *     [--fields '{json}']
 *   template fill plan --phase N       Create pre-filled PLAN.md
 *     [--plan M] [--type execute|tdd]
 *     [--wave N] [--fields '{json}']
 *   template fill verification         Create pre-filled VERIFICATION.md
 *     --phase N [--fields '{json}']
 *
 * State Progression:
 *   state advance-plan                 Increment plan counter
 *   state record-metric --phase N      Record execution metrics
 *     --plan M --duration Xmin
 *     [--tasks N] [--files N]
 *   state update-progress              Recalculate progress bar
 *   state add-decision --summary "..."  Add decision to STATE.md
 *     [--phase N] [--rationale "..."]
 *     [--summary-file path] [--rationale-file path]
 *   state add-blocker --text "..."     Add blocker
 *     [--text-file path]
 *   state resolve-blocker --text "..." Remove blocker
 *   state record-session               Update session continuity
 *     --stopped-at "..."
 *     [--resume-file path]
 *
 * Compound Commands (workflow-specific initialization):
 *   init execute-phase <phase>         All context for execute-phase workflow
 *   init plan-phase <phase>            All context for plan-phase workflow
 *   init new-project                   All context for new-project workflow
 *   init new-milestone                 All context for new-milestone workflow
 *   init quick <description>           All context for quick workflow
 *   init resume                        All context for resume-project workflow
 *   init verify-work <phase>           All context for verify-work workflow
 *   init phase-op <phase>              Generic phase operation context
 *   init todos [area]                  All context for todo workflows
 *   init milestone-op                  All context for milestone operations
 *   init map-codebase                  All context for map-codebase workflow
 *   init progress                      All context for progress workflow
 *
 * Documentation:
 *   docs-init                            Project context for docs-update workflow
 *
 * Learnings:
 *   learnings list                       List all global learnings (JSON)
 *   learnings query --tag <tag>          Query learnings by tag
 *   learnings copy                       Copy from current project's LEARNINGS.md
 *   learnings prune --older-than <dur>   Remove entries older than duration (e.g. 90d)
 *   learnings delete <id>                Delete a learning by ID
 *
 * Loop Extension Point Queries (ADR-857 phase 3c):
 *   loop render-hooks <point>            Resolve + render active Capability hooks at a loop point
 *                                        Returns JSON envelope { point, activeHooks, rendered }
 *                                        Valid points: discuss:pre/post, plan:pre/post,
 *                                        execute:pre/wave:pre/wave:post/post, verify:pre/post, ship:pre/post
 *
 * Capability State (ADR-857 phase 4b):
 *   capability state [--config-dir <path>]  Resolve per-capability install/surface/hook-activation state
 *                                           Returns JSON envelope { runtimeConfigDir, capabilities[] }
 *                                           --config-dir: runtime config dir (default: auto-detect current runtime)
 *
 * GSD-2 Migration:
 *   from-gsd2 [--path <dir>] [--force] [--dry-run]
 *             Import a GSD-2 (.gsd/) project back to GSD v1 (.planning/) format
 */

const fs = require('fs');
const path = require('path');
const { ExitError, runMain } = require('./lib/cli-exit.cjs');
const io = require('./lib/io.cjs');
const { error, ERROR_REASON, setJsonErrorMode, output } = io;
const projectRoot = require('./lib/project-root.cjs');
// Resolve findProjectRoot lazily at call time rather than binding it at module
// load. It is sourced from project-root.cjs; a call-time lookup is robust
// against any require/load-ordering edge where the export isn't bound yet
// when this entrypoint is first required (#604).
const findProjectRoot = (...args) => projectRoot.findProjectRoot(...args);
const { getActiveWorkstream } = require('./lib/planning-workspace.cjs');
const { resolveActiveWorkstream, applyResolvedWorkstreamEnv } = require('./lib/active-workstream-store.cjs');
const state = require('./lib/state.cjs');
const phase = require('./lib/phase.cjs');
const roadmap = require('./lib/roadmap.cjs');
const verify = require('./lib/verify.cjs');
const config = require('./lib/config.cjs');
const template = require('./lib/template.cjs');
const milestone = require('./lib/milestone.cjs');
const commands = require('./lib/commands.cjs');
const init = require('./lib/init.cjs');
const frontmatter = require('./lib/frontmatter.cjs');
const workstream = require('./lib/workstream.cjs');
const docs = require('./lib/docs.cjs');
const learnings = require('./lib/learnings.cjs');
const gapChecker = require('./lib/gap-checker.cjs');
const { routeStateCommand } = require('./lib/state-command-router.cjs');
const { routeVerifyCommand } = require('./lib/verify-command-router.cjs');
const { routeVerificationCommand } = require('./lib/verification-command-router.cjs');
const verification = require('./lib/verification.cjs');
const { routeInitCommand } = require('./lib/init-command-router.cjs');
const loopResolver = require('./lib/loop-resolver.cjs');
const capabilityState = require('./lib/capability-state.cjs');
const capabilityWriter = require('./lib/capability-writer.cjs');
const { routePhaseCommand } = require('./lib/phase-command-router.cjs');
const { routePhasesCommand } = require('./lib/phases-command-router.cjs');
const { routeValidateCommand } = require('./lib/validate-command-router.cjs');
const { routeRoadmapCommand } = require('./lib/roadmap-command-router.cjs');
const { routeAgentCommand } = require('./lib/agent-command-router.cjs');
const { routeCheckCommand } = require('./lib/check-command-router.cjs');
const { routeTaskCommand } = require('./lib/task-command-router.cjs');
const { parseNamedArgs, parseMultiwordArg } = require('./lib/command-arg-projection.cjs');
const { cmdGitBaseBranch } = require('./lib/git-base-branch.cjs');
const { getEffectiveAuthority, classifyDriftSeverity } = require('./lib/plan-drift-guard.cjs');

// ─── Bridge collapsed (Phase 4) ────────────────────────────────────────────────
// Non-family commands now run through their CJS handlers directly. Keep the
// helper contract so existing call sites remain unchanged during the phase
// sequence; it always returns false so callers fall through to CJS.

/**
 * Retired bridge-era shim for non-family dispatch.
 *
 * Always returns false so command handlers continue down the CJS path.
 * Kept only to avoid churn while legacy call sites are being deleted.
 *
 * @param {object} opts
 * @param {string} opts.registryCommand - legacy bridge placeholder
 * @param {string[]} opts.registryArgs - legacy bridge placeholder
 * @param {string} opts.legacyCommand - original gsd-tools command name
 * @param {string[]} opts.legacyArgs - original args
 * @param {string} opts.cwd - project dir
 * @param {boolean} opts.raw - raw output mode
 * @param {Function} opts.error - error reporter
 * @param {Function} opts.output - output emitter (output)
 */
function _dispatchNonFamily({ registryCommand, registryArgs, legacyCommand, legacyArgs, cwd, raw, error, output }) {
  void registryCommand;
  void registryArgs;
  void legacyCommand;
  void legacyArgs;
  void cwd;
  void raw;
  void error;
  void output;
  return false;
}

// ─── ADR-959: Capability Command Dispatch ─────────────────────────────────────

/**
 * Dispatch a command via the capability registry's commandFamilies index.
 *
 * Consulted in the `default` case of `runCommand` BEFORE the unknown-command
 * error is emitted. Returns:
 *   true  — command was "consumed" (found in registry, or a dispatch error was
 *            emitted); "Unknown command" is suppressed in all consumed cases.
 *   false — command not found in the registry (including prototype-pollution
 *            guard hits and missing/empty commandFamilies); caller falls through
 *            to the existing unknown-command error path.
 * Behavior-preserving when commandFamilies is empty ({}).
 *
 * Injectable for tests:
 * - `registry` defaults to require('./lib/capability-registry.cjs')
 * - `requireModule` defaults to a confinement-checked loader that resolves the
 *   module path relative to bin/lib/ and asserts it stays within that directory
 *   before requiring — defense-in-depth against corrupted/hand-edited registry entries.
 *
 * @param {object}   opts
 * @param {string}   opts.command        The command name (top-level gsd-tools command)
 * @param {string[]} opts.args           Remaining args passed to the router
 * @param {string}   opts.cwd            Project working directory
 * @param {boolean}  opts.raw            Raw output mode flag
 * @param {Function} opts.error          Error reporter (io.error)
 * @param {object}   [opts.registry]     Injectable registry (for tests)
 * @param {Function} [opts.requireModule] Injectable module loader (for tests)
 * @returns {boolean} true if the command was dispatched, false otherwise
 */
function dispatchCapabilityCommand({ command, args, cwd, raw, error, registry, requireModule }) {
  // Prototype-pollution guard: reject reserved property names as command keys
  if (command === '__proto__' || command === 'constructor' || command === 'prototype') {
    return false;
  }

  // Resolve defaults (injectable for tests)
  const reg = registry !== undefined ? registry : require('./lib/capability-registry.cjs');

  // Default requireModule: confined to bin/lib/ — validate the module name is a
  // safe bare .cjs basename (no path separators, no directory traversal), then
  // resolve and assert confinement, then require the RESOLVED absolute path so
  // the checked representation and the required representation are identical.
  const libDir = path.join(__dirname, 'lib');
  const defaultRequireModule = function (m) {
    // Step 1: validate m is a bare .cjs basename — same conservative pattern the
    // generator uses. Rejects any value with path separators (/, \, ..) or
    // missing the .cjs extension before we even touch the filesystem.
    if (typeof m !== 'string' || !/^[A-Za-z0-9._-]+\.cjs$/.test(m)) {
      throw new Error('capability module must be a bare .cjs basename: ' + JSON.stringify(m));
    }
    // Step 2: confinement check — belt-and-suspenders even after the basename
    // validation above. Resolved path must be inside libDir (not equal to it,
    // and must start with libDir + sep so "libDir-suffix" can't sneak through).
    const resolved = path.resolve(libDir, m);
    if (resolved === libDir || !resolved.startsWith(libDir + path.sep)) {
      throw new Error('capability module path escapes bin/lib/: ' + JSON.stringify(m));
    }
    // Step 3: require the resolved absolute path — the SAME representation that
    // was checked above, not the concatenated './lib/' + m string.
    return require(resolved);
  };
  const loadModule = requireModule !== undefined ? requireModule : defaultRequireModule;

  // Look up the command family in the registry
  const families = reg && reg.commandFamilies;
  if (!families || typeof families !== 'object') return false;

  const entry = families[command];
  if (!entry || typeof entry !== 'object') return false;

  // Resolve and call the router
  let mod;
  try {
    mod = loadModule(entry.module);
  } catch (_) {
    // Module not found, load error, or confinement violation — surface a
    // diagnostic and return true (consumed) so "Unknown command" is suppressed.
    error('capability command "' + command + '" module "' + entry.module + '" failed to load');
    return true; // consumed — don't emit "Unknown command"
  }

  // Own-property guard: prevent invoking inherited prototype methods
  // (constructor, toString, hasOwnProperty, etc.) as a router when the registry
  // entry names one of those. Must come before the typeof check.
  if (!mod || !Object.prototype.hasOwnProperty.call(mod, entry.router)) {
    error('capability command "' + command + '" router "' + entry.router + '" is not an own export of module "' + entry.module + '"');
    return true; // consumed — don't emit "Unknown command"
  }
  const fn = mod[entry.router];
  if (typeof fn !== 'function') {
    // Router export not found — surface a diagnostic and return true (consumed)
    // so "Unknown command" is suppressed.
    error('capability command "' + command + '" router "' + entry.router + '" is not a function in module "' + entry.module + '"');
    return true; // consumed — don't emit "Unknown command"
  }

  let _result;
  try {
    _result = fn({ args, cwd, raw, error });
  } catch (e) {
    if (e instanceof ExitError) throw e; // intentional structured error from the router (honors --json-errors) — propagate untouched
    error(
      'capability command "' + command + '" router "' + entry.router + '" in module "' + entry.module + '" threw: ' + (e && e.message ? e.message : String(e)),
      ERROR_REASON.SDK_FAIL_FAST,
    );
  }
  if (_result && typeof _result.then === 'function') {
    error(
      'capability command "' + command + '" router "' + entry.router + '" in module "' + entry.module + '" must be synchronous (returned a Promise); async capability routers are not supported.',
      ERROR_REASON.SDK_FAIL_FAST,
    );
  }
  return true;
}

// ─── Arg parsing helpers ──────────────────────────────────────────────────────

// ─── CLI Router ───────────────────────────────────────────────────────────────

async function main() {
  let args = process.argv.slice(2);

  // --json-errors / GSD_JSON_ERRORS=1: when active, error() emits structured
  // JSON ({ ok: false, reason: <ERROR_REASON code>, message }) to stderr
  // instead of "Error: <text>". Lets test suites assert on typed reason codes
  // per CONTRIBUTING.md "Prohibited: Raw Text Matching" (#2974).
  //
  // Detect early — before any flag parsing that can fire error() — so even
  // --cwd and workstream-resolution failures emit structured stderr (#3310).
  // The argv splice must happen here too, otherwise the dispatcher below sees
  // "--json-errors" as an unknown command. Default off — human operators keep
  // their plain-text diagnostic.
  const jsonErrorsIdx = args.indexOf('--json-errors');
  if (jsonErrorsIdx !== -1) {
    setJsonErrorMode(true);
    args.splice(jsonErrorsIdx, 1);
  } else if (process.env.GSD_JSON_ERRORS === '1') {
    setJsonErrorMode(true);
  }

  // Optional cwd override for sandboxed subagents running outside project root.
  let cwd = process.cwd();
  const cwdEqArg = args.find(arg => arg.startsWith('--cwd='));
  const cwdIdx = args.indexOf('--cwd');
  if (cwdEqArg) {
    const value = cwdEqArg.slice('--cwd='.length).trim();
    if (!value) error('Missing value for --cwd', ERROR_REASON.USAGE);
    args.splice(args.indexOf(cwdEqArg), 1);
    cwd = path.resolve(value);
  } else if (cwdIdx !== -1) {
    const value = args[cwdIdx + 1];
    if (!value || value.startsWith('--')) error('Missing value for --cwd', ERROR_REASON.USAGE);
    args.splice(cwdIdx, 2);
    cwd = path.resolve(value);
  }

  if (!fs.existsSync(cwd) || !fs.statSync(cwd).isDirectory()) {
    error(`Invalid --cwd: ${cwd}`, ERROR_REASON.USAGE);
  }

  // Resolve worktree root: in a linked worktree, .planning/ lives in the main worktree.
  // However, in monorepo worktrees where the subdirectory itself owns .planning/,
  // skip worktree resolution — the CWD is already the correct project root.
  const { resolveWorktreeRoot } = require('./lib/worktree-safety.cjs');
  if (!fs.existsSync(path.join(cwd, '.planning'))) {
    const worktreeRoot = resolveWorktreeRoot(cwd);
    if (worktreeRoot !== cwd) {
      cwd = worktreeRoot;
    }
  }

  // Optional workstream override for parallel milestone work.
  // Priority: --ws flag > GSD_WORKSTREAM env var > session/shared pointer > null.
  let workstreamContext = null;
  try {
    workstreamContext = resolveActiveWorkstream(cwd, args, process.env, {
      getStored: getActiveWorkstream,
    });
    args = workstreamContext.args;
    // Set env var so all modules (planningDir, planningPaths) auto-resolve workstream paths.
    applyResolvedWorkstreamEnv(workstreamContext, process.env);
  } catch (err) {
    error(err.message || String(err));
  }

  const rawIndex = args.indexOf('--raw');
  const raw = rawIndex !== -1;
  if (rawIndex !== -1) args.splice(rawIndex, 1);

  // --pick <name>: extract a single field from JSON output (replaces jq dependency).
  // Supports dot-notation (e.g., --pick workflow.research) and bracket notation
  // for arrays (e.g., --pick directories[-1]).
  const pickIdx = args.indexOf('--pick');
  let pickField = null;
  if (pickIdx !== -1) {
    pickField = args[pickIdx + 1];
    if (!pickField || pickField.startsWith('--')) error('Missing value for --pick', ERROR_REASON.USAGE);
    args.splice(pickIdx, 2);
  }

  // --default <value>: for config-get, return this value instead of erroring
  // when the key is absent. Allows workflows to express optional config reads
  // without defensive `2>/dev/null || true` boilerplate (#1893).
  const defaultIdx = args.indexOf('--default');
  let defaultValue = undefined;
  if (defaultIdx !== -1) {
    defaultValue = args[defaultIdx + 1];
    if (defaultValue === undefined) defaultValue = '';
    args.splice(defaultIdx, 2);
  }

  let command = args[0];

  // Accept `query` as a meta-prefix for canonical dotted/spaced commands.
  // Workflows may call `node gsd-tools.cjs query <command>` directly.
  if (command === 'query') {
    args.shift();
    command = args[0];
  }

  // #3243: accept dotted canonical form (e.g. `state.update`) as well as the
  // spaced form (`state update`). Some workflow callers pass the dotted
  // canonical form directly; this normalization keeps both forms valid.
  //
  // Split on the FIRST dot only — `check.decision-coverage-plan` becomes
  // command='check', args=['check','decision-coverage-plan',...rest].
  // Guard: head and rest must both be non-empty (rejects leading-dot args like
  // ".hidden" and bare-dot ".").
  const originalCommand = command; // preserved for "Unknown command" suggestion
  if (typeof command === 'string' && command.includes('.')) {
    const dotIdx = command.indexOf('.');
    const head = command.slice(0, dotIdx);
    const rest = command.slice(dotIdx + 1);
    if (head && rest) {
      command = head;
      args = [head, rest, ...args.slice(1)];
    }
  }

  // Top-level usage string — emitted by `gsd-tools` (no args) and by
  // `gsd-tools --help` / any `--help` request below.
  // CR feedback: the command list must enumerate every top-level command
  // supported by the dispatcher so `--help` is actually useful for
  // discovery; previously it was a partial subset that didn't include
  // phase / roadmap / milestone / progress / etc.
  const TOP_LEVEL_USAGE = 'Usage: gsd-tools <command> [args] [--raw] [--pick <field>] [--cwd <path>] [--ws <name>] [--json-errors]\n' +
    'Commands: agent, agent-skills, audit-open, audit-uat, check, check-commit, commit, commit-to-subrepo, ' +
    'config-ensure-section, config-get, config-new-project, config-path, config-set, migrate-config, ' +
    'current-timestamp, detect-custom-files, docs-init, drift-guard, effort, extract-messages, find-phase, ' +
    'from-gsd2, frontmatter, gap-analysis, generate-claude-md, generate-claude-profile, ' +
    'generate-dev-preferences, generate-slug, graphify, history-digest, init, intel, ' +
    'capability, classify-confidence, git, learnings, list-todos, loop, milestone, package-legitimacy, phase, phase-plan-index, phases, profile-questionnaire, ' +
    'profile-sample, progress, prompt-budget, requirements, research-plan, research-store, resolve-granularity, resolve-model, roadmap, scaffold, state, ' +
    'task, template, user-story, validate, verify, verify-path-exists, verify-summary, workstream, worktree\n\n' +
    'Global flags:\n' +
    '  --raw              Emit raw output without post-processing\n' +
    '  --pick <field>     Extract a single field from JSON output (dot/bracket notation)\n' +
    '  --cwd <path>       Override working directory for project-root resolution\n' +
    '  --ws <name>        Override active workstream (or set GSD_WORKSTREAM)\n' +
    '  --json-errors      Emit structured JSON error objects on stderr (or set GSD_JSON_ERRORS=1)\n\n' +
    'For command-specific argument requirements, invoke the command without args ' +
    '(e.g. `gsd-tools phase add`) — the resulting error lists what is required.';

  if (!command) {
    error(TOP_LEVEL_USAGE);
  }

  // #3019: a `--help` / `-h` flag in argv must render the top-level usage
  // and exit 0 — not error out with "Unknown flag". The previous shape
  // erred on agent-hallucinated flags, but it also blocked humans from
  // discovering the command surface via subcommand help requests routed
  // through this dispatcher. Rendering top-level usage on --help is strictly
  // better UX than the old short-circuit that printed unrelated usage text.
  const HELP_FLAGS = new Set(['-h', '--help', '-?', '--h', '--usage']);
  if (args.some((a) => HELP_FLAGS.has(a))) {
    process.stdout.write(TOP_LEVEL_USAGE + '\n');
    return;
  }

  // Reject version flags. AI agents sometimes hallucinate --version on tool
  // invocations; silently ignoring it can cause destructive operations to
  // proceed unchecked. (Help flags are handled above.)
  const NEVER_VALID_FLAGS = new Set(['--version', '-v']);
  for (const arg of args) {
    if (NEVER_VALID_FLAGS.has(arg)) {
      error(`Unknown flag: ${arg}\ngsd-tools does not accept version flags. Run "gsd-tools" with no arguments for usage.`, ERROR_REASON.USAGE);
    }
  }

  // Multi-repo guard: resolve project root for commands that read/write .planning/.
  // Skip for pure-utility commands that don't touch .planning/ to avoid unnecessary
  // filesystem traversal on every invocation.
  // 'loop' and 'capability' are intentionally NOT in SKIP_ROOT_RESOLUTION.
  // Both are registry/config queries that resolve activation via
  // .planning/config.json; they need the project root (cwd) for correct
  // `when` key resolution. If one is ever moved to SKIP_ROOT_RESOLUTION,
  // move the other at the same time (keep them consistent).
  const SKIP_ROOT_RESOLUTION = new Set([
    'generate-slug', 'current-timestamp', 'verify-path-exists',
    'verify-summary', 'template', 'frontmatter', 'detect-custom-files',
    'worktree', 'prompt-budget',
    'research-store', 'research-plan', 'package-legitimacy', 'classify-confidence',
    'user-story', // pure string validation — no .planning/ access needed
  ]);
  if (!SKIP_ROOT_RESOLUTION.has(command)) {
    cwd = findProjectRoot(cwd);
  }

  // When --pick is active, capture stdout and extract the requested field.
  if (pickField) {
    const captured = await captureStdoutSyncWrites(async () => {
      await runCommand(command, args, cwd, raw, defaultValue, originalCommand, workstreamContext);
    });
    const resolved = resolveAtFileOutput(captured);
    try {
      const obj = JSON.parse(resolved);
      const value = extractField(obj, pickField);
      const result = value === null || value === undefined ? '' : String(value);
      fs.writeSync(1, result);
    } catch {
      fs.writeSync(1, captured);
    }
    return;
  }

  // Intercept stdout to transparently resolve @file: references (#1891).
  // io.cjs output() writes @file:<path> when JSON > 50KB. The --pick path
  // already resolves this, but the normal path wrote @file: to stdout, forcing
  // every workflow to have a bash-specific `if [[ "$INIT" == @file:* ]]` check
  // that breaks on PowerShell and other non-bash shells.
  const captured = await captureStdoutSyncWrites(async () => {
    await runCommand(command, args, cwd, raw, defaultValue, originalCommand, workstreamContext);
  });
  fs.writeSync(1, resolveAtFileOutput(captured));
}

function captureStdoutSyncWrites(run) {
  const originalWriteSync = fs.writeSync;
  let captured = '';

  fs.writeSync = function patchedWriteSync(fd, data, ...rest) {
    if (fd === 1) {
      if (Buffer.isBuffer(data)) {
        captured += data.toString('utf-8');
        return data.length;
      }
      const text = String(data);
      captured += text;
      let encoding = 'utf-8';
      if (typeof rest[1] === 'string') encoding = rest[1];
      return Buffer.byteLength(text, encoding);
    }
    return originalWriteSync.call(fs, fd, data, ...rest);
  };

  const restore = () => {
    fs.writeSync = originalWriteSync;
  };

  return Promise.resolve()
    .then(() => run())
    .then(() => {
      restore();
      return captured;
    }, (err) => {
      restore();
      throw err;
    });
}

function resolveAtFileOutput(captured) {
  if (!captured.startsWith('@file:')) return captured;
  return fs.readFileSync(captured.slice(6), 'utf-8');
}

/**
 * Extract a field from an object using dot-notation and bracket syntax.
 * Supports: 'field', 'parent.child', 'arr[-1]', 'arr[0]'
 */
function extractField(obj, fieldPath) {
  const parts = fieldPath.split('.');
  let current = obj;
  for (const part of parts) {
    if (current === null || current === undefined) return undefined;
    const bracketMatch = part.match(/^(.+?)\[(-?\d+)]$/);
    if (bracketMatch) {
      const key = bracketMatch[1];
      const index = parseInt(bracketMatch[2], 10);
      current = current[key];
      if (!Array.isArray(current)) return undefined;
      current = index < 0 ? current[current.length + index] : current[index];
    } else {
      current = current[part];
    }
  }
  return current;
}

async function runCommand(command, args, cwd, raw, defaultValue, originalCommand, workstreamContext = null) {
  switch (command) {
    case 'agent': {
      routeAgentCommand({ args, raw });
      break;
    }

    case 'check': {
      routeCheckCommand({ args, cwd, raw });
      break;
    }

    case 'state': {
      routeStateCommand({
        state,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    case 'resolve-model': {
      commands.cmdResolveModel(cwd, args[1], raw);
      break;
    }

    case 'resolve-granularity': {
      // Parse optional --granularity <val> flag (space form only); positional is phase-type.
      // The =form (--granularity=<val>) is intentionally not supported: parseNamedArgs and
      // the /gsd:plan-phase + init plan-phase paths accept only the space form, so supporting
      // = here alone would create an inconsistency (#703).
      const granArgs = args.slice(1);
      let granOverride;
      const granPositionals = [];
      for (let i = 0; i < granArgs.length; i++) {
        const a = granArgs[i];
        if (a === '--granularity' && granArgs[i + 1] !== undefined && !granArgs[i + 1].startsWith('--')) {
          if (granOverride === undefined) { granOverride = granArgs[++i]; } else { ++i; }
        } else {
          granPositionals.push(a);
        }
      }
      commands.cmdResolveGranularity(cwd, granPositionals[0], raw, granOverride);
      break;
    }

    case 'resolve-execution': {
      // Deterministic flag parsing: consume --flag <value> pairs first,
      // then the AGENT is the single remaining positional.
      // Supports both orderings: <agent> --flag val  AND  --flag val <agent>.
      // Also supports --flag=value form (same convention as --cwd= above).
      const execArgs = args.slice(1);
      let effortOverride;
      let fastModeOverride;
      let attempt;
      const positionals = [];
      for (let i = 0; i < execArgs.length; i++) {
        const a = execArgs[i];
        // --effort=<val> form
        if (a.startsWith('--effort=')) {
          effortOverride = a.slice('--effort='.length);
          continue;
        }
        // --fast-mode=<val> form
        if (a.startsWith('--fast-mode=')) {
          const v = a.slice('--fast-mode='.length);
          fastModeOverride = v === 'true' ? true : v === 'false' ? false : undefined;
          continue;
        }
        // --attempt=<val> form
        if (a.startsWith('--attempt=')) {
          const v = a.slice('--attempt='.length);
          const n = parseInt(v, 10);
          if (!Number.isInteger(n) || n < 0) error('--attempt requires a non-negative integer', ERROR_REASON.USAGE);
          attempt = n;
          continue;
        }
        // --effort <val>
        if (a === '--effort') {
          const val = execArgs[i + 1];
          if (val === undefined || val.startsWith('--')) error('Missing value for --effort', ERROR_REASON.USAGE);
          effortOverride = val;
          i++;
          continue;
        }
        // --fast-mode <val>
        if (a === '--fast-mode') {
          const val = execArgs[i + 1];
          if (val === undefined || val.startsWith('--')) error('Missing value for --fast-mode', ERROR_REASON.USAGE);
          fastModeOverride = val === 'true' ? true : val === 'false' ? false : undefined;
          i++;
          continue;
        }
        // --attempt <val>
        if (a === '--attempt') {
          const val = execArgs[i + 1];
          if (val === undefined || val.startsWith('--')) error('Missing value for --attempt', ERROR_REASON.USAGE);
          const n = parseInt(val, 10);
          if (!Number.isInteger(n) || n < 0) error('--attempt requires a non-negative integer', ERROR_REASON.USAGE);
          attempt = n;
          i++;
          continue;
        }
        // --raw is handled by top-level arg processing; skip it here
        if (a === '--raw') continue;
        // Unknown flag
        if (a.startsWith('-')) error(`Unknown flag for resolve-execution: ${a}`, ERROR_REASON.USAGE);
        // Positional
        positionals.push(a);
      }
      if (positionals.length === 0) error('agent-type required', ERROR_REASON.USAGE);
      if (positionals.length > 1) error(`resolve-execution requires exactly one agent-type argument; got: ${positionals.join(', ')}`, ERROR_REASON.USAGE);
      const agentTypeArg = positionals[0];
      commands.cmdResolveExecution(cwd, agentTypeArg, raw, {
        effortOverride,
        fastModeOverride,
        attempt,
      });
      break;
    }

    case 'find-phase': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      // SDK handler: findPhase in sdk/src/query/phase.ts.
      const handled = _dispatchNonFamily({
        registryCommand: 'find-phase',
        registryArgs: args.slice(1),
        legacyCommand: 'find-phase',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) phase.cmdFindPhase(cwd, args[1], raw);
      break;
    }

    case 'commit': {
      const amend = args.includes('--amend');
      const noVerify = args.includes('--no-verify');
      const filesIndex = args.indexOf('--files');
      // Collect all positional args between command name and first flag,
      // then join them — handles both quoted ("multi word msg") and
      // unquoted (multi word msg) invocations from different shells
      const endIndex = filesIndex !== -1 ? filesIndex : args.length;
      const messageArgs = args.slice(1, endIndex).filter(a => !a.startsWith('--'));
      const message = messageArgs.join(' ') || undefined;
      const files = filesIndex !== -1 ? args.slice(filesIndex + 1).filter(a => !a.startsWith('--')) : [];
      commands.cmdCommit(cwd, message, files, raw, amend, noVerify);
      break;
    }

    case 'check-commit': {
      commands.cmdCheckCommit(cwd, raw);
      break;
    }

    case 'commit-to-subrepo': {
      const message = args[1];
      const filesIndex = args.indexOf('--files');
      const files = filesIndex !== -1 ? args.slice(filesIndex + 1).filter(a => !a.startsWith('--')) : [];
      commands.cmdCommitToSubrepo(cwd, message, files, raw);
      break;
    }

    case 'verify-summary': {
      const summaryPath = args[1];
      const countIndex = args.indexOf('--check-count');
      const checkCount = countIndex !== -1 ? parseInt(args[countIndex + 1], 10) : 2;
      verify.cmdVerifySummary(cwd, summaryPath, checkCount, raw);
      break;
    }

    case 'template': {
      const subcommand = args[1];
      if (subcommand === 'select') {
        template.cmdTemplateSelect(cwd, args[2], raw);
      } else if (subcommand === 'fill') {
        const templateType = args[2];
        const { phase, plan, name, type, wave, fields: fieldsRaw } = parseNamedArgs(args, ['phase', 'plan', 'name', 'type', 'wave', 'fields']);
        let fields = {};
        if (fieldsRaw) {
          const { safeJsonParse } = require('./lib/security.cjs');
          const result = safeJsonParse(fieldsRaw, { label: '--fields' });
          if (!result.ok) error(result.error);
          fields = result.value;
        }
        template.cmdTemplateFill(cwd, templateType, {
          phase, plan, name, fields,
          type: type || 'execute',
          wave: wave || '1',
        }, raw);
      } else {
        error('Unknown template subcommand. Available: select, fill', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'task': {
      routeTaskCommand({ args, cwd, raw });
      break;
    }

    case 'frontmatter': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      // SDK handler: sdk/src/query/frontmatter.ts + frontmatter-mutation.ts.
      // CJS fallback: frontmatter.cjs (cooperating sibling).
      const subcommand = args[1];
      const file = args[2];
      const FRONTMATTER_SDK_MAP = {
        get: 'frontmatter.get',
        set: 'frontmatter.set',
        merge: 'frontmatter.merge',
        validate: 'frontmatter.validate',
      };
      if (subcommand in FRONTMATTER_SDK_MAP) {
        const handled = _dispatchNonFamily({
          registryCommand: FRONTMATTER_SDK_MAP[subcommand],
          registryArgs: args.slice(2),
          legacyCommand: 'frontmatter',
          legacyArgs: args.slice(1),
          cwd,
          raw,
          error,
          output: output,
        });
        if (handled) break;
      }
      // CJS fallback (SDK unavailable or unknown subcommand)
      if (subcommand === 'get') {
        frontmatter.cmdFrontmatterGet(cwd, file, parseNamedArgs(args, ['field']).field, raw);
      } else if (subcommand === 'set') {
        const { field, value } = parseNamedArgs(args, ['field', 'value']);
        frontmatter.cmdFrontmatterSet(cwd, file, field, value !== null ? value : undefined, raw);
      } else if (subcommand === 'merge') {
        frontmatter.cmdFrontmatterMerge(cwd, file, parseNamedArgs(args, ['data']).data, raw);
      } else if (subcommand === 'validate') {
        frontmatter.cmdFrontmatterValidate(cwd, file, parseNamedArgs(args, ['schema']).schema, raw);
      } else {
        error('Unknown frontmatter subcommand. Available: get, set, merge, validate', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'verify': {
      routeVerifyCommand({
        verify,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    // ─── Verification Status ───────────────────────────────────────────────
    //
    // verification status <phaseDir>
    //   Read the first *-VERIFICATION.md in phaseDir and return
    //   { status, next_action, next_command } routing result.
    //
    // Note: `verification` (reads verifier-emitted status) is distinct from
    // `verify` (runs verification checks like plan-structure/artifacts).

    case 'verification': {
      routeVerificationCommand({
        verification,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    case 'generate-slug': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      // SDK handler: generateSlug in sdk/src/query/utils.ts.
      const handled = _dispatchNonFamily({
        registryCommand: 'generate-slug',
        registryArgs: args.slice(1),
        legacyCommand: 'generate-slug',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) commands.cmdGenerateSlug(args[1], raw);
      break;
    }

    case 'current-timestamp': {
      // Keep this command on the CJS fast path.
      // Rationale: it is a pure local formatter and avoids SDK bridge startup
      // in tight subprocess loops where Windows CI has shown intermittent
      // native crashes (0xC0000005 / 3221225477).
      commands.cmdCurrentTimestamp(args[1] || 'full', raw);
      break;
    }

    case 'list-todos': {
      commands.cmdListTodos(cwd, args[1], raw);
      break;
    }

    case 'verify-path-exists': {
      commands.cmdVerifyPathExists(cwd, args[1], raw);
      break;
    }

    case 'config-ensure-section': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs. The catalog rebinds
      // 'config-ensure-section' to configNewProject in
      // sdk/src/query/command-static-catalog-foundation.ts, restoring the
      // legacy "no-arg full default init" contract on the SDK path
      // (configEnsureSection itself stays available as an unbound single-
      // section helper for future SDK callers).
      const handled = _dispatchNonFamily({
        registryCommand: 'config-ensure-section',
        registryArgs: args.slice(1),
        legacyCommand: 'config-ensure-section',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) config.cmdConfigEnsureSection(cwd, raw);
      break;
    }

    case 'config-set': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      const handled = _dispatchNonFamily({
        registryCommand: 'config-set',
        registryArgs: args.slice(1),
        legacyCommand: 'config-set',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) config.cmdConfigSet(cwd, args[1], args[2], raw);
      break;
    }

    case "config-set-model-profile": {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      const handled = _dispatchNonFamily({
        registryCommand: 'config-set-model-profile',
        registryArgs: args.slice(1),
        legacyCommand: 'config-set-model-profile',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) config.cmdConfigSetModelProfile(cwd, args[1], raw);
      break;
    }

    case 'config-get': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      // The SDK handler supports --default via the registry args (args.slice(1)
      // contains the key; defaultValue is handled by the SDK via the --default
      // flag which was already stripped from args and held in defaultValue).
      // Pass the full original args.slice(1) so the SDK sees the key; the
      // defaultValue from the flag is in the global defaultValue variable above.
      // Since the SDK handler reads --default from registryArgs, re-inject it.
      const configGetSdkArgs = defaultValue !== undefined
        ? [args[1], '--default', defaultValue]
        : args.slice(1);
      const handled = _dispatchNonFamily({
        registryCommand: 'config-get',
        registryArgs: configGetSdkArgs,
        legacyCommand: 'config-get',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) config.cmdConfigGet(cwd, args[1], raw, defaultValue);
      break;
    }

    case 'config-new-project': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      const handled = _dispatchNonFamily({
        registryCommand: 'config-new-project',
        registryArgs: args.slice(1),
        legacyCommand: 'config-new-project',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) config.cmdConfigNewProject(cwd, args[1], raw);
      break;
    }

    case 'config-path': {
      // CJS-native: config-path returns the filesystem path to config.json.
      // The SDK handler (configPath) also exists but requires a projectDir that
      // is already resolved. Both produce identical output; keeping CJS here is
      // simpler and avoids sync-bridge overhead for a trivial path lookup.
      config.cmdConfigPath(cwd, raw, workstreamContext);
      break;
    }

    case 'migrate-config': {
      // CJS-native: migrate-config wraps the Configuration Module migrateOnDisk()
      // which is async and mutates the filesystem. No SDK counterpart exists in
      // the command registry (it's a one-shot migration utility). Must await.
      await config.cmdMigrateConfig(cwd, raw);
      break;
    }

    case 'agent-skills': {
      // --json emits typed IR { agent_type, block, skills_count } for test assertions
      // (#455). Default (no flag) outputs raw XML so workflow shell expansions work.
      const jsonIdx = args.indexOf('--json');
      const agentSkillsJsonMode = jsonIdx !== -1;
      if (agentSkillsJsonMode) args.splice(jsonIdx, 1);
      init.cmdAgentSkills(cwd, args[1], raw, agentSkillsJsonMode);
      break;
    }

    case 'skill-manifest': {
      init.cmdSkillManifest(cwd, args, raw);
      break;
    }

    case 'history-digest': {
      commands.cmdHistoryDigest(cwd, raw);
      break;
    }

    case 'phases': {
      routePhasesCommand({
        phase,
        milestone,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    case 'roadmap': {
      routeRoadmapCommand({
        roadmap,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    case 'requirements': {
      const subcommand = args[1];
      if (subcommand === 'mark-complete') {
        milestone.cmdRequirementsMarkComplete(cwd, args.slice(2), raw);
      } else {
        error('Unknown requirements subcommand. Available: mark-complete', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'gap-analysis': {
      // Post-planning gap checker (#2493) — unified REQUIREMENTS.md +
      // CONTEXT.md <decisions> coverage report against PLAN.md files.
      gapChecker.cmdGapAnalysis(cwd, args.slice(1), raw);
      break;
    }

    case 'phase': {
      routePhaseCommand({
        phase,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    case 'milestone': {
      const subcommand = args[1];
      if (subcommand === 'complete') {
        const milestoneName = parseMultiwordArg(args, 'name');
        const archivePhases = args.includes('--archive-phases');
        const force = args.includes('--force');
        milestone.cmdMilestoneComplete(cwd, args[2], { name: milestoneName, archivePhases, force }, raw);
      } else {
        error('Unknown milestone subcommand. Available: complete', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'validate': {
      routeValidateCommand({
        verify,
        args,
        cwd,
        raw,
        output: output,
        error,
      });
      break;
    }

    case 'progress': {
      const subcommand = args[1] || 'json';
      commands.cmdProgressRender(cwd, subcommand, raw);
      break;
    }

    case 'uat': {
      const subcommand = args[1];
      const uat = require('./lib/uat.cjs');
      if (subcommand === 'render-checkpoint') {
        const options = parseNamedArgs(args, ['file']);
        uat.cmdRenderCheckpoint(cwd, options, raw);
      } else {
        error('Unknown uat subcommand. Available: render-checkpoint', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'stats': {
      const subcommand = args[1] || 'json';
      commands.cmdStats(cwd, subcommand, raw);
      break;
    }

    case 'todo': {
      const subcommand = args[1];
      if (subcommand === 'complete') {
        commands.cmdTodoComplete(cwd, args[2], raw);
      } else if (subcommand === 'match-phase') {
        commands.cmdTodoMatchPhase(cwd, args[2], raw);
      } else {
        error('Unknown todo subcommand. Available: complete, match-phase', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'scaffold': {
      const scaffoldType = args[1];
      const scaffoldOptions = {
        phase: parseNamedArgs(args, ['phase']).phase,
        name: parseMultiwordArg(args, 'name'),
      };
      commands.cmdScaffold(cwd, scaffoldType, scaffoldOptions, raw);
      break;
    }

    case 'init': {
      routeInitCommand({
        init,
        args,
        cwd,
        raw,
        error,
      });
      break;
    }

    case 'loop': {
      // loop render-hooks <point>
      const loopSubcommand = args[1];
      if (loopSubcommand === 'render-hooks') {
        let loopConfigDir = null;
        const configDirEqArg = args.find(arg => arg.startsWith('--config-dir='));
        const configDirIdx = args.indexOf('--config-dir');
        if (configDirEqArg) {
          const value = configDirEqArg.slice('--config-dir='.length).trim();
          if (!value) error('Missing value for --config-dir', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          loopConfigDir = value;
        } else if (configDirIdx !== -1) {
          const value = args[configDirIdx + 1];
          if (!value || value.startsWith('--')) {
            error('Missing value for --config-dir', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          }
          loopConfigDir = value;
        }
        // --active-cap <capId>: parse and validate before delegating
        let loopActiveCap = undefined;
        const activeCapEqArg = args.find(arg => arg.startsWith('--active-cap='));
        const activeCapIdx = args.indexOf('--active-cap');
        if (activeCapEqArg) {
          const value = activeCapEqArg.slice('--active-cap='.length).trim();
          if (!value) error('Missing value for --active-cap (e.g. --active-cap tdd)', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          loopActiveCap = value;
        } else if (activeCapIdx !== -1) {
          const value = args[activeCapIdx + 1];
          if (!value || value.startsWith('--')) {
            error('Missing value for --active-cap (e.g. --active-cap tdd)', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          }
          loopActiveCap = value;
        }
        loopResolver.cmdLoopRenderHooks(cwd, args[2], raw, {
          configDir: loopConfigDir ? path.resolve(loopConfigDir) : undefined,
          activeCap: loopActiveCap,
        });
      } else {
        error(
          `Unknown loop subcommand: ${loopSubcommand}. Available: render-hooks`,
          ERROR_REASON ? ERROR_REASON.SDK_UNKNOWN_COMMAND : undefined,
        );
      }
      break;
    }

    case 'capability': {
      // capability state [--config-dir <path>]
      // Root resolution: 'capability' is NOT in SKIP_ROOT_RESOLUTION for the
      // same reason 'loop' is not: both are registry/config queries that need
      // the project root (cwd) for .planning/config.json activation resolution.
      // If 'loop' were ever added to SKIP_ROOT_RESOLUTION, 'capability' should
      // be added at the same time to keep them consistent.
      const capSubcommand = args[1];
      if (capSubcommand === 'state') {
        const configDirIdx = args.indexOf('--config-dir');
        let configDir = null;
        if (configDirIdx !== -1) {
          const configDirVal = args[configDirIdx + 1];
          // Validate that --config-dir has a following non-flag value.
          if (!configDirVal || configDirVal.startsWith('--')) {
            error('Missing value for --config-dir', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          }
          configDir = configDirVal;
        }
        const resolvedConfigDir = configDir ? path.resolve(configDir) : null;
        capabilityState.cmdCapabilityState(cwd, resolvedConfigDir, raw, {});
      } else if (capSubcommand === 'set') {
        // capability set <id> [--on|--off|--enable|--disable] [--gate <key>=<bool>]... [--config-dir <dir>] [--runtime <r>] [--scope <s>]
        const capId = args[2];
        if (!capId || capId.startsWith('--')) {
          error('Missing capability id for: capability set <id>', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
        }
        // Parse --config-dir
        const setConfigDirIdx = args.indexOf('--config-dir');
        let setConfigDir = null;
        if (setConfigDirIdx !== -1) {
          const setConfigDirVal = args[setConfigDirIdx + 1];
          if (!setConfigDirVal || setConfigDirVal.startsWith('--')) {
            error('Missing value for --config-dir', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          }
          setConfigDir = setConfigDirVal;
        }
        const resolvedSetConfigDir = setConfigDir ? path.resolve(setConfigDir) : null;
        // Parse --on/--enable and --off/--disable (mutually exclusive)
        const hasOn = args.includes('--on') || args.includes('--enable');
        const hasOff = args.includes('--off') || args.includes('--disable');
        if (hasOn && hasOff) {
          error('Conflicting flags: --on/--enable and --off/--disable cannot both be present', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
        }
        let setEnabled;
        if (hasOn) {
          setEnabled = true;
        } else if (hasOff) {
          setEnabled = false;
        }
        // Parse --gate <key>=<bool> (repeatable)
        const setGates = {};
        for (let gi = 0; gi < args.length; gi++) {
          if (args[gi] === '--gate') {
            const gateVal = args[gi + 1];
            if (!gateVal || gateVal.startsWith('--')) {
              error('Missing value for --gate (expected <key>=<true|false>)', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
            }
            const eqIdx = gateVal.indexOf('=');
            if (eqIdx === -1) {
              error(`Malformed --gate value "${gateVal}": expected <key>=<true|false>`, ERROR_REASON ? ERROR_REASON.USAGE : undefined);
            }
            const gateKey = gateVal.slice(0, eqIdx);
            const gateBoolStr = gateVal.slice(eqIdx + 1);
            if (gateBoolStr !== 'true' && gateBoolStr !== 'false') {
              error(`Malformed --gate value "${gateVal}": bool must be true or false`, ERROR_REASON ? ERROR_REASON.USAGE : undefined);
            }
            setGates[gateKey] = gateBoolStr === 'true';
            gi++; // skip consumed value
          }
        }
        // Parse --runtime and --scope (validate that values are present and not flags)
        const runtimeIdx = args.indexOf('--runtime');
        let setRuntime;
        if (runtimeIdx !== -1) {
          const runtimeVal = args[runtimeIdx + 1];
          if (!runtimeVal || runtimeVal.startsWith('--')) {
            error('Missing value for --runtime', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          }
          setRuntime = runtimeVal;
        }
        const scopeIdx = args.indexOf('--scope');
        let setScope;
        if (scopeIdx !== -1) {
          const scopeVal = args[scopeIdx + 1];
          if (!scopeVal || scopeVal.startsWith('--')) {
            error('Missing value for --scope', ERROR_REASON ? ERROR_REASON.USAGE : undefined);
          }
          setScope = scopeVal;
        }
        capabilityWriter.cmdCapabilitySet(
          cwd,
          resolvedSetConfigDir,
          capId,
          { enabled: setEnabled, gates: Object.keys(setGates).length > 0 ? setGates : undefined, runtime: setRuntime, scope: setScope },
          raw,
        );
      } else {
        error(
          `Unknown capability subcommand: ${capSubcommand}. Available: state, set`,
          ERROR_REASON ? ERROR_REASON.SDK_UNKNOWN_COMMAND : undefined,
        );
      }
      break;
    }

    case 'phase-plan-index': {
      phase.cmdPhasePlanIndex(cwd, args[1], raw);
      break;
    }

    case 'state-snapshot': {
      state.cmdStateSnapshot(cwd, raw);
      break;
    }

    case 'summary-extract': {
      const summaryPath = args[1];
      const fieldsIndex = args.indexOf('--fields');
      const fields = fieldsIndex !== -1 ? args[fieldsIndex + 1].split(',') : null;
      commands.cmdSummaryExtract(cwd, summaryPath, fields, raw);
      break;
    }

    case 'websearch': {
      const query = args[1];
      const limitIdx = args.indexOf('--limit');
      const freshnessIdx = args.indexOf('--freshness');
      await commands.cmdWebsearch(query, {
        limit: limitIdx !== -1 ? parseInt(args[limitIdx + 1], 10) : 10,
        freshness: freshnessIdx !== -1 ? args[freshnessIdx + 1] : null,
      }, raw);
      break;
    }

    case 'workstream': {
      const subcommand = args[1];
      if (subcommand === 'create') {
        const migrateNameIdx = args.indexOf('--migrate-name');
        const noMigrate = args.includes('--no-migrate');
        workstream.cmdWorkstreamCreate(cwd, args[2], {
          migrate: !noMigrate,
          migrateName: migrateNameIdx !== -1 ? args[migrateNameIdx + 1] : null,
        }, raw);
      } else if (subcommand === 'list') {
        workstream.cmdWorkstreamList(cwd, raw);
      } else if (subcommand === 'status') {
        workstream.cmdWorkstreamStatus(cwd, args[2], raw);
      } else if (subcommand === 'complete') {
        workstream.cmdWorkstreamComplete(cwd, args[2], {}, raw);
      } else if (subcommand === 'set') {
        workstream.cmdWorkstreamSet(cwd, args[2], raw);
      } else if (subcommand === 'get') {
        workstream.cmdWorkstreamGet(cwd, raw);
      } else if (subcommand === 'progress') {
        workstream.cmdWorkstreamProgress(cwd, raw);
      } else {
        error('Unknown workstream subcommand. Available: create, list, status, complete, set, get, progress', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    case 'worktree': {
      const subcommand = args[1];
      const worktreeSafety = require('./lib/worktree-safety.cjs');
      if (subcommand === 'cleanup-wave') {
        worktreeSafety.cmdWorktreeCleanupWave(cwd, args.slice(2));
      } else if (subcommand === 'reap-orphans') {
        worktreeSafety.cmdWorktreeReapOrphans(cwd);
      } else if (subcommand === 'base-check') {
        require('./lib/worktree-base-ref.cjs').cmdWorktreeBaseCheck(cwd, args.slice(2));
      } else if (subcommand === 'set-baseref') {
        require('./lib/worktree-base-ref.cjs').cmdWorktreeSetBaseRef(cwd, args.slice(2));
      } else {
        error('Unknown worktree subcommand. Available: cleanup-wave, reap-orphans, base-check, set-baseref', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    // ─── Documentation ────────────────────────────────────────────────────

    case 'docs-init': {
      // Phase 6 (#3575): dispatch via SDK executeForCjs when available.
      // SDK handler: docsInit in sdk/src/query/docs-init.ts.
      const handled = _dispatchNonFamily({
        registryCommand: 'docs-init',
        registryArgs: args.slice(1),
        legacyCommand: 'docs-init',
        legacyArgs: args.slice(1),
        cwd,
        raw,
        error,
        output: output,
      });
      if (!handled) docs.cmdDocsInit(cwd, raw);
      break;
    }

    // ─── Learnings ─────────────────────────────────────────────────────────

    case 'learnings': {
      const subcommand = args[1];
      if (subcommand === 'list') {
        learnings.cmdLearningsList(raw);
      } else if (subcommand === 'query') {
        const tagIdx = args.indexOf('--tag');
        const tag = tagIdx !== -1 ? args[tagIdx + 1] : null;
        if (!tag) error('Usage: gsd-tools learnings query --tag <tag>', ERROR_REASON.USAGE);
        learnings.cmdLearningsQuery(tag, raw);
      } else if (subcommand === 'copy') {
        learnings.cmdLearningsCopy(cwd, raw);
      } else if (subcommand === 'prune') {
        const olderIdx = args.indexOf('--older-than');
        const olderThan = olderIdx !== -1 ? args[olderIdx + 1] : null;
        if (!olderThan) error('Usage: gsd-tools learnings prune --older-than <duration>', ERROR_REASON.USAGE);
        learnings.cmdLearningsPrune(olderThan, raw);
      } else if (subcommand === 'delete') {
        const id = args[2];
        if (!id) error('Usage: gsd-tools learnings delete <id>', ERROR_REASON.USAGE);
        learnings.cmdLearningsDelete(id, raw);
      } else {
        error('Unknown learnings subcommand. Available: list, query, copy, prune, delete', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    // ─── teams-status ──────────────────────────────────────────────────────
    // Read-only detector for claude-code's experimental agent-teams feature.
    // issue #1355: stop gsd-core hanging silently under claude-code agent-teams.
    // No capability registration needed — this is a diagnostic query command,
    // not a feature capability.
    case 'teams-status': {
      const teamsStatus = require('./lib/teams-status.cjs');
      teamsStatus.cmdTeamsStatus(cwd, { active: args.includes('--active') });
      break;
    }

    // ─── detect-custom-files ───────────────────────────────────────────────
    // CJS-native: no SDK counterpart exists in the command registry.
    // detect-custom-files reads a gsd-file-manifest.json against the
    // live filesystem to identify user-added files. It is installer-specific
    // logic that has no async query equivalent in the SDK.
    //
    // Detect user-added files inside GSD-managed directories that are not
    // tracked in gsd-file-manifest.json. Used by the update workflow to back
    // up custom files before the installer wipes those directories.
    //
    // This replaces the fragile bash pattern:
    //   MANIFEST_FILES=$(node -e "require('$RUNTIME_DIR/...')" 2>/dev/null)
    //   ${filepath#$RUNTIME_DIR/}   # unreliable path stripping
    // which silently returns CUSTOM_COUNT=0 when $RUNTIME_DIR is unset or
    // when the stripped path does not match the manifest key format (#1997).

    case 'detect-custom-files': {
      const configDirIdx = args.indexOf('--config-dir');
      const configDir = configDirIdx !== -1 ? args[configDirIdx + 1] : null;
      if (!configDir) {
        error('Usage: gsd-tools detect-custom-files --config-dir <path>', ERROR_REASON.USAGE);
      }
      const resolvedConfigDir = path.resolve(configDir);
      if (!fs.existsSync(resolvedConfigDir)) {
        error(`Config directory not found: ${resolvedConfigDir}`, ERROR_REASON.USAGE);
      }

      const manifestPath = path.join(resolvedConfigDir, 'gsd-file-manifest.json');
      if (!fs.existsSync(manifestPath)) {
        // No manifest — cannot determine what is custom. Return empty list
        // (same behaviour as saveLocalPatches in install.js when no manifest).
        const out = { custom_files: [], custom_count: 0, manifest_found: false };
        process.stdout.write(JSON.stringify(out, null, 2));
        break;
      }

      let manifest;
      try {
        manifest = JSON.parse(await fs.promises.readFile(manifestPath, 'utf8'));
      } catch {
        const out = { custom_files: [], custom_count: 0, manifest_found: false, error: 'manifest parse error' };
        process.stdout.write(JSON.stringify(out, null, 2));
        break;
      }

      const manifestKeys = new Set(Object.keys(manifest.files || {}));

      // GSD-managed directories to scan for user-added files. Whole-owned
      // roots are wiped recursively; shared runtime roots are pruned by the
      // same gsd-* top-level prefix used by install.js _removeGsdEntries.
      const GSD_WHOLE_MANAGED_DIRS = [
        'gsd-core',
        path.join('commands', 'gsd'),
      ];
      const GSD_PREFIX_MANAGED_DIRS = [
        'agents',
        'hooks',
        'skills',
      ];

      function collectCustomFiles(dir, baseDir, manifestKeys, out) {
        if (!fs.existsSync(dir)) return;
        const stat = fs.statSync(dir);
        if (stat.isFile()) {
          const relPath = path.relative(baseDir, dir).replace(/\\/g, '/');
          if (!manifestKeys.has(relPath)) {
            out.push(relPath);
          }
          return;
        }
        if (!stat.isDirectory()) return;
        for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
          const fullPath = path.join(dir, entry.name);
          if (entry.isDirectory()) {
            collectCustomFiles(fullPath, baseDir, manifestKeys, out);
            continue;
          }
          // Use forward slashes for cross-platform manifest key compatibility
          const relPath = path.relative(baseDir, fullPath).replace(/\\/g, '/');
          if (!manifestKeys.has(relPath)) {
            out.push(relPath);
          }
        }
      }

      const customFiles = [];
      for (const managedDir of GSD_WHOLE_MANAGED_DIRS) {
        const absDir = path.join(resolvedConfigDir, managedDir);
        if (!fs.existsSync(absDir)) continue;
        collectCustomFiles(absDir, resolvedConfigDir, manifestKeys, customFiles);
      }
      for (const managedDir of GSD_PREFIX_MANAGED_DIRS) {
        const absDir = path.join(resolvedConfigDir, managedDir);
        if (!fs.existsSync(absDir)) continue;
        for (const entry of fs.readdirSync(absDir, { withFileTypes: true })) {
          if (!entry.name.startsWith('gsd-')) continue;
          collectCustomFiles(path.join(absDir, entry.name), resolvedConfigDir, manifestKeys, customFiles);
        }
      }

      const out = {
        custom_files: customFiles,
        custom_count: customFiles.length,
        manifest_found: true,
        manifest_version: manifest.version || null,
      };
      process.stdout.write(JSON.stringify(out, null, 2));
      break;
    }

    // ─── GSD-2 Reverse Migration ───────────────────────────────────────────

    case 'from-gsd2': {
      const gsd2Import = require('./lib/gsd2-import.cjs');
      gsd2Import.cmdFromGsd2(args.slice(1), cwd, raw);
      break;
    }

    // ─── Prompt Budget ────────────────────────────────────────────────────
    //
    // Assemble and deterministically trim review prompt sections to fit a
    // token budget. Used by the /gsd-review workflow before dispatching to
    // small-context local model servers (Ollama, llama.cpp, LM Studio).
    //
    // Required flags:
    //   --budget <N>            Token budget (integer > 0)
    //   --instructions-file <path>  Review instructions
    //   --roadmap-file <path>   Roadmap section
    //   --plan-file <path>      Plan file (may be repeated)
    //   --output-prompt <path>  Write trimmed prompt here
    //   --output-metadata <path> Write metadata JSON here
    //
    // Optional flags:
    //   --safety-margin-pct <N>     Default 10
    //   --project-md-head-lines <N> Default 40
    //   --project-file <path>
    //   --context-file <path>
    //   --research-file <path>
    //   --requirements-file <path>
    //
    // Exit codes:
    //   0  success (trim or no-trim)
    //   1  invocation error (missing required arg, missing file, invalid budget)
    //   2  hardFailed: prompt cannot fit effective budget after trim policy

    case 'prompt-budget': {
      const promptBudget = require('./lib/prompt-budget.cjs');

      // ── Collect multi-value --plan-file flags ──────────────────────────
      const planFiles = [];
      for (let i = 1; i < args.length; i++) {
        if (args[i] === '--plan-file' && args[i + 1] && !args[i + 1].startsWith('--')) {
          planFiles.push(args[i + 1]);
          i++;
        }
      }

      // ── Parse single-value flags ───────────────────────────────────────
      const flagMap = new Map();
      for (let i = 1; i < args.length; i++) {
        const current = args[i];
        const next = args[i + 1];
        if (!current.startsWith('--')) continue;
        if (!next || next.startsWith('--')) {
          if (!flagMap.has(current)) flagMap.set(current, null);
          continue;
        }
        if (!flagMap.has(current)) flagMap.set(current, next);
        i++;
      }
      const getFlag = (flag) => flagMap.get(flag) ?? null;

      const budgetStr = getFlag('--budget');
      const instructionsFile = getFlag('--instructions-file');
      const roadmapFile = getFlag('--roadmap-file');
      const outputPromptFile = getFlag('--output-prompt');
      const outputMetadataFile = getFlag('--output-metadata');
      const safetyMarginStr = getFlag('--safety-margin-pct');
      const projectMdHeadLinesStr = getFlag('--project-md-head-lines');
      const projectFile = getFlag('--project-file');
      const contextFile = getFlag('--context-file');
      const researchFile = getFlag('--research-file');
      const requirementsFile = getFlag('--requirements-file');

      // ── Validate required args ─────────────────────────────────────────
      if (!budgetStr) {
        throw new ExitError(1, 'Error: --budget <N> is required');
      }
      const budget = parseInt(budgetStr, 10);
      if (!Number.isFinite(budget) || budget <= 0) {
        throw new ExitError(1, 'Error: --budget must be a positive integer');
      }
      if (!instructionsFile) {
        throw new ExitError(1, 'Error: --instructions-file <path> is required');
      }
      if (!roadmapFile) {
        throw new ExitError(1, 'Error: --roadmap-file <path> is required');
      }
      if (planFiles.length === 0) {
        throw new ExitError(1, 'Error: at least one --plan-file <path> is required');
      }
      if (!outputPromptFile) {
        throw new ExitError(1, 'Error: --output-prompt <path> is required');
      }
      if (!outputMetadataFile) {
        throw new ExitError(1, 'Error: --output-metadata <path> is required');
      }

      // ── Validate and read required files ──────────────────────────────
      async function readRequired(filePath, flagName) {
        const resolved = path.resolve(filePath);
        try {
          return await fs.promises.readFile(resolved, 'utf8');
        } catch (err) {
          if (err && err.code === 'ENOENT') {
            throw new ExitError(1, `Error: file not found for ${flagName}: ${resolved}`);
          }
          throw new ExitError(1, `Error: cannot read file for ${flagName}: ${resolved}`);
        }
      }

      async function readOptional(filePath) {
        if (!filePath) return null;
        const resolved = path.resolve(filePath);
        try {
          return await fs.promises.readFile(resolved, 'utf8');
        } catch (err) {
          if (err && err.code === 'ENOENT') return null;
          throw new ExitError(1, `Error: cannot read optional file: ${resolved}`);
        }
      }

      const instructions = await readRequired(instructionsFile, '--instructions-file');
      const roadmap = await readRequired(roadmapFile, '--roadmap-file');
      const plans = await Promise.all(planFiles.map(async (p) => {
        const resolved = path.resolve(p);
        try {
          const content = await fs.promises.readFile(resolved, 'utf8');
          return { file: path.basename(p), content };
        } catch (err) {
          if (err && err.code === 'ENOENT') {
            throw new ExitError(1, `Error: plan file not found: ${resolved}`);
          }
          throw new ExitError(1, `Error: cannot read plan file: ${resolved}`);
        }
      }));

      const projectMd = await readOptional(projectFile);
      const context = await readOptional(contextFile);
      const research = await readOptional(researchFile);
      const requirements = await readOptional(requirementsFile);

      // ── Build options ─────────────────────────────────────────────────
      const options = {};
      if (safetyMarginStr !== null) {
        const pct = parseInt(safetyMarginStr, 10);
        if (Number.isFinite(pct)) options.safetyMarginPct = pct;
      }
      if (projectMdHeadLinesStr !== null) {
        const lines = parseInt(projectMdHeadLinesStr, 10);
        if (Number.isFinite(lines)) options.projectMdHeadLines = lines;
      }

      // ── Call applyBudget ──────────────────────────────────────────────
      const sections = { instructions, roadmap, plans, projectMd, context, research, requirements };
      const { prompt, metadata } = promptBudget.applyBudget({ sections, budget, options });

      // ── Write outputs ─────────────────────────────────────────────────
      await fs.promises.writeFile(path.resolve(outputMetadataFile), JSON.stringify(metadata, null, 2));
      await fs.promises.writeFile(path.resolve(outputPromptFile), prompt);

      if (metadata.hardFailed) {
        throw new ExitError(2);
      }
      break;
    }

    case 'update-context': {
      // #498: resolve the installed GSD version, scope, runtime, and config dir
      // for /gsd:update. Replaces ~280 lines of inline bash in update.md with a
      // tested projection. Emits the contract as JSON: { installedVersion,
      // scope, runtime, gsdDir }. Optional --config-dir / --runtime carry the
      // workflow's execution_context hints (the one thing only it can know).
      const { loadUpdateContext } = require('./lib/update-context.cjs');
      const ucArgs = args.slice(1);
      let preferredConfigDir = '';
      let preferredRuntime = '';
      for (let i = 0; i < ucArgs.length; i++) {
        const a = ucArgs[i];
        if (a.startsWith('--config-dir=')) { preferredConfigDir = a.slice('--config-dir='.length); continue; }
        if (a.startsWith('--runtime=')) { preferredRuntime = a.slice('--runtime='.length); continue; }
        if (a === '--config-dir') {
          const v = ucArgs[i + 1];
          if (v === undefined || v.startsWith('--')) error('Missing value for --config-dir', ERROR_REASON.USAGE);
          preferredConfigDir = v; i++; continue;
        }
        if (a === '--runtime') {
          const v = ucArgs[i + 1];
          if (v === undefined || v.startsWith('--')) error('Missing value for --runtime', ERROR_REASON.USAGE);
          preferredRuntime = v; i++; continue;
        }
        if (a === '--json') continue; // JSON is the only output; accepted for symmetry
        if (a.startsWith('-')) error(`Unknown flag for update-context: ${a}`, ERROR_REASON.USAGE);
      }
      const ctx = loadUpdateContext({ preferredConfigDir, preferredRuntime });
      process.stdout.write(JSON.stringify(ctx) + '\n');
      break;
    }

    // ─── Research Store ────────────────────────────────────────────────────
    //
    // research-store get <key> [--kind <k>]
    //   -> getResearch(cwd, key, { homeDir }); searches both tiers; output(result, raw)
    //   (--kind is accepted for backward compatibility but no longer drives tier selection)
    // research-store put <key> --content <str> --source <s> --provider <p>
    //                           --confidence <c> --kind <k>
    //   -> putResearch(cwd, key, { content, source, provider, confidence, kind })
    //
    // Tier is derived from source: 'curated' source writes to process.env.HOME/.gsd/research-cache;
    // all other sources write to cwd/.planning/research/.cache.
    // Tests may override the home directory by setting the HOME env var.

    case 'research-store': {
      const researchStore = require('./lib/research-store.cjs');
      const subcommand = args[1];
      const homeDir = process.env.HOME || require('os').homedir();
      if (subcommand === 'get') {
        const key = args[2];
        if (!key || key.startsWith('--')) {
          error('Usage: gsd-tools research-store get <key> [--kind <k>]', ERROR_REASON.USAGE);
        }
        if (!researchStore.isValidResearchKey(key)) {
          error('research-store: <key> must be a 64-char sha256 hex (use research-plan to obtain keys)', ERROR_REASON.USAGE);
        }
        // --kind is accepted but no longer drives tier selection; getResearch searches both tiers
        const result = researchStore.getResearch(cwd, key, { homeDir });
        output(result, raw);
      } else if (subcommand === 'put') {
        const key = args[2];
        if (!key || key.startsWith('--')) {
          error('Usage: gsd-tools research-store put <key> --content <str> --source <s> --provider <p> --confidence <c> --kind <k>', ERROR_REASON.USAGE);
        }
        if (!researchStore.isValidResearchKey(key)) {
          error('research-store: <key> must be a 64-char sha256 hex (use research-plan to obtain keys)', ERROR_REASON.USAGE);
        }
        const contentIdx = args.indexOf('--content');
        const sourceIdx = args.indexOf('--source');
        const providerIdx = args.indexOf('--provider');
        const confidenceIdx = args.indexOf('--confidence');
        const kindIdx = args.indexOf('--kind');
        // For each flag, if the following value is missing or itself starts with '--', reject.
        function getFlagValue(idx, flagName) {
          if (idx === -1) return null;
          const val = args[idx + 1];
          if (val === undefined || val.startsWith('--')) {
            error(`research-store put: missing value for ${flagName}`, ERROR_REASON.USAGE);
          }
          return val;
        }
        const content = getFlagValue(contentIdx, '--content');
        const source = getFlagValue(sourceIdx, '--source');
        const provider = getFlagValue(providerIdx, '--provider');
        const confidence = getFlagValue(confidenceIdx, '--confidence');
        const kind = getFlagValue(kindIdx, '--kind');
        if (!content || !source || !provider || !confidence || !kind) {
          error('Usage: gsd-tools research-store put <key> --content <str> --source <s> --provider <p> --confidence <c> --kind <k>', ERROR_REASON.USAGE);
        }
        const entry = researchStore.putResearch(cwd, key, { content, source, provider, confidence, kind }, { homeDir });
        output(entry, raw);
      } else {
        error('Unknown research-store subcommand. Available: get, put', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    // ─── Research Plan ─────────────────────────────────────────────────────
    //
    // research-plan --input <path>
    //   Read+JSON.parse file; call planResearch({ questions, ecosystem, config, cwd })
    //   { ecosystem, config, questions: [{ text, kind, library?, version? }] }

    case 'research-plan': {
      const researchProvider = require('./lib/research-provider.cjs');
      const inputIdx = args.indexOf('--input');
      const inputPath = inputIdx !== -1 ? args[inputIdx + 1] : null;
      if (!inputPath || inputPath.startsWith('--')) {
        error('Usage: gsd-tools research-plan --input <path>', ERROR_REASON.USAGE);
      }
      let planInput;
      try {
        const raw_ = fs.readFileSync(path.resolve(inputPath), 'utf8');
        planInput = JSON.parse(raw_);
      } catch (readErr) {
        error(`research-plan: cannot read/parse --input file: ${inputPath}`, ERROR_REASON.USAGE);
      }
      if (planInput === null || typeof planInput !== 'object' || Array.isArray(planInput)) {
        error('research-plan: --input must be an object with a questions array', ERROR_REASON.USAGE);
      }
      if (!Array.isArray(planInput.questions)) {
        error('research-plan: --input must be an object with a questions array', ERROR_REASON.USAGE);
      }
      const { ecosystem = '', config: planConfig = {}, questions } = planInput;
      const homeDir = process.env.HOME || require('os').homedir();
      const plan = researchProvider.planResearch({ questions, ecosystem, config: planConfig, cwd, homeDir });
      output(plan, raw);
      break;
    }

    // ─── Classify Confidence ──────────────────────────────────────────────
    //
    // classify-confidence --provider <id> [--package <name> --ecosystem <npm|pypi|crates>] [--verified]
    //   -> classifyConfidence({ provider, verifiedAgainstOfficial, legitimacyVerdict }); output(result, raw)
    //
    // legitimacyVerdict is CODE-COMPUTED via checkPackages — never caller-supplied — so an agent cannot self-assert OK→HIGH.

    case 'classify-confidence': {
      const researchProvider = require('./lib/research-provider.cjs');
      const providerIdx = args.indexOf('--provider');
      const provider = providerIdx !== -1 ? args[providerIdx + 1] : null;
      if (!provider || provider.startsWith('--')) {
        error('Usage: gsd-tools query classify-confidence --provider <id> [--package <name> --ecosystem <npm|pypi|crates>] [--verified]', ERROR_REASON.USAGE);
      }
      const verified = args.includes('--verified');
      const pkgIdx = args.indexOf('--package');
      const pkg = pkgIdx !== -1 ? args[pkgIdx + 1] : null;
      const ecoIdx = args.indexOf('--ecosystem');
      const ecosystem = ecoIdx !== -1 ? args[ecoIdx + 1] : null;
      let legitimacyVerdict = null;
      if (pkg && (!pkg.startsWith('--'))) {
        const VALID_ECOSYSTEMS = new Set(['npm', 'pypi', 'crates']);
        if (!ecosystem || ecosystem.startsWith('--') || !VALID_ECOSYSTEMS.has(ecosystem)) {
          error('Usage: gsd-tools query classify-confidence --provider <id> [--package <name> --ecosystem <npm|pypi|crates>] [--verified]', ERROR_REASON.USAGE);
        }
        const pkgLegitimacy = require('./lib/package-legitimacy.cjs');
        const results = await pkgLegitimacy.checkPackages({ ecosystem, packages: [pkg] }, {});
        legitimacyVerdict = results[0] ? results[0].verdict : null;
      }
      const confidence = researchProvider.classifyConfidence({ provider, verifiedAgainstOfficial: verified, legitimacyVerdict });
      output({ provider, package: pkg || null, ecosystem: ecosystem || null, legitimacyVerdict, verified, confidence }, raw);
      break;
    }

    // ─── Package Legitimacy ────────────────────────────────────────────────
    //
    // package-legitimacy check --ecosystem <eco> <pkg1> <pkg2> ...
    //
    // checkPackages is ASYNC. This entire runCommand function is async, so
    // we can await directly. On rejection we call error() which exits.

    case 'package-legitimacy': {
      const pkgLegitimacy = require('./lib/package-legitimacy.cjs');
      const subcommand = args[1];
      if (subcommand !== 'check') {
        error('Unknown package-legitimacy subcommand. Available: check', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      const ecoIdx = args.indexOf('--ecosystem');
      const ecosystem = ecoIdx !== -1 ? args[ecoIdx + 1] : null;
      const VALID_ECOSYSTEMS = new Set(['npm', 'pypi', 'crates']);
      if (!ecosystem || !VALID_ECOSYSTEMS.has(ecosystem)) {
        error('Usage: gsd-tools package-legitimacy check --ecosystem <npm|pypi|crates> <pkg1> ...', ERROR_REASON.USAGE);
      }
      // Collect positional package names.
      // Only --ecosystem takes a value. Every non-flag arg is a package name.
      // Any unknown --flag is a usage error (do not silently skip+consume the next arg).
      const packages = [];
      for (let i = 2; i < args.length; i++) {
        const a = args[i];
        if (a === '--ecosystem') { i++; continue; }
        if (a.startsWith('--')) {
          error(`package-legitimacy: unknown flag ${a}`, ERROR_REASON.USAGE);
        }
        packages.push(a);
      }
      if (packages.length === 0) {
        error('Usage: gsd-tools package-legitimacy check --ecosystem <eco> <pkg1> <pkg2> ...', ERROR_REASON.USAGE);
      }
      let pkgResults;
      try {
        pkgResults = await pkgLegitimacy.checkPackages({ ecosystem, packages }, {});
      } catch (pkgErr) {
        error(`package-legitimacy: ${pkgErr && pkgErr.message ? pkgErr.message : String(pkgErr)}`, ERROR_REASON.UNKNOWN);
      }
      output(pkgResults, raw);
      break;
    }

    case 'effort': {
      const subcommand = args[1];
      if (subcommand === 'sync') {
        const effortSyncArgs = args.slice(2);
        let dryRun = true;
        let effortSyncConfigDir;
        let effortSyncRuntime;
        for (let i = 0; i < effortSyncArgs.length; i++) {
          const a = effortSyncArgs[i];
          if (a === '--apply') { dryRun = false; continue; }
          if (a === '--dry-run') { dryRun = true; continue; }
          if (a.startsWith('--config-dir=')) { effortSyncConfigDir = a.slice('--config-dir='.length); continue; }
          if (a === '--config-dir') {
            const v = effortSyncArgs[i + 1];
            if (!v || v.startsWith('--')) error('Missing value for --config-dir', ERROR_REASON.USAGE);
            effortSyncConfigDir = v; i++; continue;
          }
          if (a.startsWith('--runtime=')) { effortSyncRuntime = a.slice('--runtime='.length); continue; }
          if (a === '--runtime') {
            const v = effortSyncArgs[i + 1];
            if (!v || v.startsWith('--')) error('Missing value for --runtime', ERROR_REASON.USAGE);
            effortSyncRuntime = v; i++; continue;
          }
          if (a === '--raw') continue;
          if (a.startsWith('-')) error(`Unknown flag for effort sync: ${a}`, ERROR_REASON.USAGE);
          error(`effort sync takes no positional arguments; got: ${a}`, ERROR_REASON.USAGE);
        }
        commands.cmdEffortSync(cwd, raw, { dryRun, configDir: effortSyncConfigDir, runtime: effortSyncRuntime });
      } else {
        error('Unknown effort subcommand. Available: sync', ERROR_REASON.SDK_UNKNOWN_COMMAND);
      }
      break;
    }

    // ─── User Story Validation (bug #1145) ────────────────────────────────────
    //
    // Invocation shapes (from mvp-phase.md and verify-work.md):
    //   gsd_run query user-story.validate --story "$USER_STORY"
    //   gsd_run query user-story.validate --story "$PHASE_GOAL" --pick valid
    //
    // Returns JSON: { valid: boolean, errors: string[], slots: { role, capability, outcome } | null }
    //   - valid: true only when the story fully matches the canonical format
    //   - errors: per-slot diagnostic strings (empty on success)
    //   - slots: extracted role/capability/outcome on success; null on failure
    //
    // Canonical format (user-story-template.md):
    //   "As a [user role], I want to [capability], so that [outcome]."
    //   Each slot must be non-empty and contain non-whitespace content.
    //
    // No .planning/ access needed — pure string validation.

    // #1146: single base-branch resolver for all forking workflows.
    // Workflows call `gsd_run query git.base-branch` (dotted form normalised to
    // command='git', args=['git','base-branch']).
    case 'git': {
      const subcommand = args[1];
      if (subcommand !== 'base-branch') {
        error(
          `Unknown git subcommand: ${subcommand || '(none)'}. Available: base-branch`,
          ERROR_REASON.SDK_UNKNOWN_COMMAND,
        );
        break;
      }
      cmdGitBaseBranch(cwd, args.slice(2));
      break;
    }

    case 'user-story': {
      const subcommand = args[1];
      if (subcommand !== 'validate') {
        error(`Unknown user-story subcommand: ${subcommand || '(none)'}. Available: validate`, ERROR_REASON.SDK_UNKNOWN_COMMAND);
        break;
      }

      const storyIdx = args.indexOf('--story');
      const story = (storyIdx !== -1 && args[storyIdx + 1] && !args[storyIdx + 1].startsWith('--'))
        ? args[storyIdx + 1]
        : '';

      // Canonical extraction regex — requires non-whitespace content in each slot
      // (\S.*? ensures the slot isn't whitespace-only).
      // Named groups: role / capability / outcome.
      const USER_STORY_RE = /^As a (\S.*?), I want to (\S.*?), so that (\S.*?)\.$/;

      const errors = [];
      const trimmed = story.trim();
      let slots = null;

      if (!trimmed) {
        errors.push('Story is empty. Required format: "As a [role], I want to [capability], so that [outcome]."');
      } else {
        // Per-clause guards produce targeted, actionable error messages before
        // attempting the full regex. Guards are ordered: role → capability → outcome → period.
        if (!/^As a \S/i.test(trimmed)) {
          errors.push('Story must start with "As a [user role]," (role must be non-empty).');
        }
        if (!/, I want to \S/i.test(trimmed)) {
          errors.push('Story must include ", I want to [capability]," (capability must be non-empty).');
        }
        if (!/, so that \S/i.test(trimmed)) {
          errors.push('Story must include ", so that [outcome]." (outcome must be non-empty).');
        }
        if (!trimmed.endsWith('.')) {
          errors.push('Story must end with a period (.).');
        }
        // Full-regex check only when per-clause guards all passed — avoids
        // redundant "format mismatch" noise on top of specific error messages.
        if (errors.length === 0) {
          const m = USER_STORY_RE.exec(trimmed);
          if (!m) {
            errors.push('Story does not match the canonical format: "As a [role], I want to [capability], so that [outcome]."');
          } else {
            slots = { role: m[1], capability: m[2], outcome: m[3] };
          }
        }
      }

      output({ valid: errors.length === 0, errors, slots }, raw);
      break;
    }

    case 'drift-guard': {
      // ADR-22: deterministic authority resolution + severity classification.
      // Subcommands:
      //   drift-guard authority                          → effective authority string
      //   drift-guard severity --status <S> [--authority <A>]  → {severity, hardBlock}
      const subcommand = args[1];

      // Read config.json directly for both plan_review.source_grounding_authority
      // and intel.enabled. Neither key is in the config-loader.cjs whitelist that
      // config-loader.cjs's loadConfig() whitelist does not return; plan_review is only in config.cjs's private
      // buildConfig(), and intel is a federated capability config key.
      let configuredAuthority = 'grep';
      let intelEnabled = false;
      try {
        const { planningDir } = require('./lib/planning-workspace.cjs');
        const cfgPath = require('path').join(planningDir(cwd), 'config.json');
        if (require('fs').existsSync(cfgPath)) {
          const rawCfg = JSON.parse(require('fs').readFileSync(cfgPath, 'utf-8'));
          if (rawCfg && rawCfg.plan_review && rawCfg.plan_review.source_grounding_authority) {
            configuredAuthority = String(rawCfg.plan_review.source_grounding_authority);
          }
          if (rawCfg && rawCfg.intel && rawCfg.intel.enabled === true) {
            intelEnabled = true;
          }
        }
      } catch {
        // not fatal — defaults apply
      }

      const effectiveAuthority = getEffectiveAuthority(configuredAuthority, intelEnabled);

      if (subcommand === 'authority') {
        // Pass rawValue as 3rd arg so --raw returns unquoted string (not JSON)
        output(effectiveAuthority, raw, effectiveAuthority);
        break;
      }

      if (subcommand === 'severity') {
        const statusIdx = args.indexOf('--status');
        const statusVal = statusIdx !== -1 ? args[statusIdx + 1] : undefined;
        if (!statusVal || statusVal.startsWith('--')) {
          error('drift-guard severity requires --status <VERIFIED|MISSING|AMBIGUOUS|UNCHECKABLE>', ERROR_REASON.SDK_UNKNOWN_COMMAND);
          break;
        }
        const authIdx = args.indexOf('--authority');
        const authVal = authIdx !== -1 ? args[authIdx + 1] : undefined;
        const authorityForClassify = (authVal && !authVal.startsWith('--'))
          ? authVal
          : effectiveAuthority;
        const result = classifyDriftSeverity({ status: statusVal, authority: authorityForClassify });
        output(result, raw);
        break;
      }

      error(
        `Unknown drift-guard subcommand: ${subcommand || '(none)'}. Available: authority, severity`,
        ERROR_REASON.SDK_UNKNOWN_COMMAND,
      );
      break;
    }

    default: {
      // ADR-959: try capability-registry dispatch before emitting the unknown-command error.
      // An unmigrated command still hits its hardcoded `case` above — untouched.
      // A migrated command's `case` is removed at cutover, so it reaches here and
      // dispatchCapabilityCommand routes it to the capability's registered router.
      // commandFamilies now includes migrated capabilities (e.g. graphify → graphify-command-router.cjs);
      // this returns true when a registered capability owns the command, false otherwise.
      if (dispatchCapabilityCommand({ command, args, cwd, raw, error })) break;

      // #3243: if the caller passed a dotted form (e.g. "foo.bar"), the shim
      // above split it so `command` here is the head ("foo"). Use
      // originalCommand to reconstruct the original dotted form and suggest
      // the spaced equivalent — surfacing a useful diagnostic instead of just
      // "Unknown command: foo".
      const wasDotted =
        typeof originalCommand === 'string' &&
        originalCommand !== command &&
        originalCommand.includes('.');
      let suggestion = '';
      if (wasDotted) {
        const dotIdx = originalCommand.indexOf('.');
        const head = originalCommand.slice(0, dotIdx);
        const rest = originalCommand.slice(dotIdx + 1);
        suggestion = ` — did you mean: "${head} ${rest}"?`;
      }
      error(`Unknown command: ${command}${suggestion}`, ERROR_REASON.SDK_UNKNOWN_COMMAND);
    }
  }
}

// ─── CLI entry point ──────────────────────────────────────────────────────────
if (require.main === module) {
  runMain(main);
}

// ─── Exports (for tests) ──────────────────────────────────────────────────────
// ADR-959: export dispatchCapabilityCommand so tests can exercise it with
// synthetic registry + requireModule injections.
module.exports = { dispatchCapabilityCommand };