[System] You are a code execution simulator.

[User]
You are reasoning about concurrent Go program execution.

Here is a Go program:
<program>
// WEAVE_META
// outcome: leak
// concurrency_pattern: mutex
// goroutine_count: 3
// expected_nondeterminism: medium
// description: Human-written GoBench bug kernel serving_2137 (leak)

package main

import (
	"os"
	"runtime/trace"
	"runtime"
	"sync"
	)

type token struct{}

type request struct {
	lock     *sync.Mutex
	accepted chan bool
}

type Breaker struct {
	pendingRequests chan token
	activeRequests  chan token
}

func (b *Breaker) Maybe(thunk func()) bool {
	var t token
	select {
	default:
		// Pending request queue is full.  Report failure.
		return false
	case b.pendingRequests <- t:
		// Pending request has capacity.
		// Wait for capacity in the active queue.
		b.activeRequests <- t
		// Defer releasing capacity in the active and pending request queue.
		defer func() { <-b.activeRequests; <-b.pendingRequests }()
		// Do the thing.
		thunk()
		// Report success
		return true
	}
}

func (b *Breaker) concurrentRequest() request {
	runtime.Gosched()

	r := request{lock: &sync.Mutex{}, accepted: make(chan bool, 1)}
	r.lock.Lock()
	var start sync.WaitGroup
	start.Add(1)
	go func() { // G2, G3
		start.Done()
		ok := b.Maybe(func() {
			r.lock.Lock() // Will block on locked mutex.
			r.lock.Unlock()
		})
		r.accepted <- ok
	}()
	start.Wait() // Ensure that the go func has had a chance to execute.
	return r
}

// Perform n requests against the breaker, returning mutexes for each
// request which succeeded, and a slice of bools for all requests.
func (b *Breaker) concurrentRequests(n int) []request {
	requests := make([]request, n)
	for i := range requests {
		requests[i] = b.concurrentRequest()
	}
	return requests
}

func NewBreaker(queueDepth, maxConcurrency int32) *Breaker {
	return &Breaker{
		pendingRequests: make(chan token, queueDepth+maxConcurrency),
		activeRequests:  make(chan token, maxConcurrency),
	}
}

func unlock(req request) {
	req.lock.Unlock()
	// Verify that function has completed
	ok := <-req.accepted
	// Requeue for next usage
	req.accepted <- ok
}

func unlockAll(requests []request) {
	for _, lc := range requests {
		unlock(lc)
	}
}

//
// G1                           G2                      G3
// b.concurrentRequests(2)
// b.concurrentRequest()
// r.lock.Lock()
//                                                      start.Done()
// start.Wait()
// b.concurrentRequest()
// r.lock.Lock()
//                              start.Done()
// start.Wait()
// unlockAll(locks)
// unlock(lc)
// req.lock.Unlock()
// ok := <-req.accepted
//                              b.Maybe()
//                              b.activeRequests <- t
//                              thunk()
//                              r.lock.Lock()
//                                                      b.Maybe()
//                                                      b.activeRequests <- t
// ----------------------------G1,G2,G3 deadlock-----------------------------
//
func main() {
	if tf := os.Getenv("WEAVE_TRACE_FILE"); tf != "" {
		f, err := os.Create(tf)
		if err == nil {
			if err := trace.Start(f); err == nil {
				defer func() { trace.Stop(); f.Close() }()
			}
		}
	}

	b := NewBreaker(1, 1)

	locks := b.concurrentRequests(2) // G1
	unlockAll(locks)
}

</program>

Here is a partial execution trace showing goroutine scheduler events so far:
<trace>
[
  {
    "event_id": 12,
    "timestamp_ns": 14788778346368,
    "event_type": "GoStart",
    "goroutine_id": 6,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 13,
    "timestamp_ns": 14788778347456,
    "event_type": "GoBlock",
    "goroutine_id": 6,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 14,
    "timestamp_ns": 14788778349248,
    "event_type": "GoBlock",
    "goroutine_id": 5,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 15,
    "timestamp_ns": 14788778351360,
    "event_type": "GoCreate",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 16,
    "timestamp_ns": 14788778363200,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 17,
    "timestamp_ns": 14788778363712,
    "event_type": "GoStart",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 18,
    "timestamp_ns": 14788778374464,
    "event_type": "GoUnblock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 19,
    "timestamp_ns": 14788778379776,
    "event_type": "GoBlock",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 20,
    "timestamp_ns": 14788778380096,
    "event_type": "GoStart",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 21,
    "timestamp_ns": 14788778380800,
    "event_type": "GoSched",
    "goroutine_id": 1,
    "goroutines": {
      "1": {
        "status": "runnable",
        "blocked_on": null,
        "locals_hint": "runtime.Gosched"
      },
      "33": {
        "status": "blocked",
        "blocked_on": "sync",
        "locals_hint": "sync.(*Mutex).Lock"
      },
      "4": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "5": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "6": {
        "status": "blocked",
        "blocked_on": "system goroutine wait",
        "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
      }
    },
    "channels": {},
    "mutexes": {}
  }
]
</trace>

The current goroutine states are:
<current_state>
{
  "event_id": 21,
  "timestamp_ns": 14788778380800,
  "event_type": "GoSched",
  "goroutine_id": 1,
  "goroutines": {
    "1": {
      "status": "runnable",
      "blocked_on": null,
      "locals_hint": "runtime.Gosched"
    },
    "33": {
      "status": "blocked",
      "blocked_on": "sync",
      "locals_hint": "sync.(*Mutex).Lock"
    },
    "4": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "5": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "6": {
      "status": "blocked",
      "blocked_on": "system goroutine wait",
      "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
    }
  },
  "channels": {},
  "mutexes": {}
}
</current_state>

Predict the next scheduler event. What happens next?
Respond in JSON only — no markdown fences, no text outside the JSON object:
{"event_type":"GoStart|GoBlock|GoUnblock|GoCreate|GoEnd|GoSched","goroutine_id":<integer>,"reasoning":"<brief explanation>","confidence":"high|medium|low"}

[Assistant] {"event_type": "GoCreate", "goroutine_id": 34}


[System] You are a code execution simulator.

[User]
You are reasoning about concurrent Go program execution.

Here is a Go program:
<program>
// WEAVE_META
// outcome: leak
// concurrency_pattern: mutex
// goroutine_count: 3
// expected_nondeterminism: medium
// description: Human-written GoBench bug kernel serving_2137 (leak)

package main

import (
	"os"
	"runtime/trace"
	"runtime"
	"sync"
	)

type token struct{}

type request struct {
	lock     *sync.Mutex
	accepted chan bool
}

type Breaker struct {
	pendingRequests chan token
	activeRequests  chan token
}

func (b *Breaker) Maybe(thunk func()) bool {
	var t token
	select {
	default:
		// Pending request queue is full.  Report failure.
		return false
	case b.pendingRequests <- t:
		// Pending request has capacity.
		// Wait for capacity in the active queue.
		b.activeRequests <- t
		// Defer releasing capacity in the active and pending request queue.
		defer func() { <-b.activeRequests; <-b.pendingRequests }()
		// Do the thing.
		thunk()
		// Report success
		return true
	}
}

func (b *Breaker) concurrentRequest() request {
	runtime.Gosched()

	r := request{lock: &sync.Mutex{}, accepted: make(chan bool, 1)}
	r.lock.Lock()
	var start sync.WaitGroup
	start.Add(1)
	go func() { // G2, G3
		start.Done()
		ok := b.Maybe(func() {
			r.lock.Lock() // Will block on locked mutex.
			r.lock.Unlock()
		})
		r.accepted <- ok
	}()
	start.Wait() // Ensure that the go func has had a chance to execute.
	return r
}

// Perform n requests against the breaker, returning mutexes for each
// request which succeeded, and a slice of bools for all requests.
func (b *Breaker) concurrentRequests(n int) []request {
	requests := make([]request, n)
	for i := range requests {
		requests[i] = b.concurrentRequest()
	}
	return requests
}

func NewBreaker(queueDepth, maxConcurrency int32) *Breaker {
	return &Breaker{
		pendingRequests: make(chan token, queueDepth+maxConcurrency),
		activeRequests:  make(chan token, maxConcurrency),
	}
}

func unlock(req request) {
	req.lock.Unlock()
	// Verify that function has completed
	ok := <-req.accepted
	// Requeue for next usage
	req.accepted <- ok
}

func unlockAll(requests []request) {
	for _, lc := range requests {
		unlock(lc)
	}
}

//
// G1                           G2                      G3
// b.concurrentRequests(2)
// b.concurrentRequest()
// r.lock.Lock()
//                                                      start.Done()
// start.Wait()
// b.concurrentRequest()
// r.lock.Lock()
//                              start.Done()
// start.Wait()
// unlockAll(locks)
// unlock(lc)
// req.lock.Unlock()
// ok := <-req.accepted
//                              b.Maybe()
//                              b.activeRequests <- t
//                              thunk()
//                              r.lock.Lock()
//                                                      b.Maybe()
//                                                      b.activeRequests <- t
// ----------------------------G1,G2,G3 deadlock-----------------------------
//
func main() {
	if tf := os.Getenv("WEAVE_TRACE_FILE"); tf != "" {
		f, err := os.Create(tf)
		if err == nil {
			if err := trace.Start(f); err == nil {
				defer func() { trace.Stop(); f.Close() }()
			}
		}
	}

	b := NewBreaker(1, 1)

	locks := b.concurrentRequests(2) // G1
	unlockAll(locks)
}

</program>

Here is a partial execution trace showing goroutine scheduler events so far:
<trace>
[
  {
    "event_id": 20,
    "timestamp_ns": 14790844788608,
    "event_type": "GoCreate",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 21,
    "timestamp_ns": 14790844790336,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 22,
    "timestamp_ns": 14790844790592,
    "event_type": "GoStart",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 23,
    "timestamp_ns": 14790844810688,
    "event_type": "GoUnblock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 24,
    "timestamp_ns": 14790844815424,
    "event_type": "GoBlock",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 25,
    "timestamp_ns": 14790844815808,
    "event_type": "GoStart",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 26,
    "timestamp_ns": 14790844817792,
    "event_type": "GoUnblock",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 27,
    "timestamp_ns": 14790844818240,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 28,
    "timestamp_ns": 14790844818496,
    "event_type": "GoStart",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 29,
    "timestamp_ns": 14790844820736,
    "event_type": "GoUnblock",
    "goroutine_id": 34,
    "goroutines": {
      "1": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "19": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "20": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "21": {
        "status": "blocked",
        "blocked_on": "system goroutine wait",
        "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
      },
      "33": {
        "status": "running",
        "blocked_on": null,
        "locals_hint": "unknown"
      },
      "34": {
        "status": "runnable",
        "blocked_on": null,
        "locals_hint": "runtime.chanrecv1"
      }
    },
    "channels": {},
    "mutexes": {}
  }
]
</trace>

The current goroutine states are:
<current_state>
{
  "event_id": 29,
  "timestamp_ns": 14790844820736,
  "event_type": "GoUnblock",
  "goroutine_id": 34,
  "goroutines": {
    "1": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "19": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "20": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "21": {
      "status": "blocked",
      "blocked_on": "system goroutine wait",
      "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
    },
    "33": {
      "status": "running",
      "blocked_on": null,
      "locals_hint": "unknown"
    },
    "34": {
      "status": "runnable",
      "blocked_on": null,
      "locals_hint": "runtime.chanrecv1"
    }
  },
  "channels": {},
  "mutexes": {}
}
</current_state>

Predict the next scheduler event. What happens next?
Respond in JSON only — no markdown fences, no text outside the JSON object:
{"event_type":"GoStart|GoBlock|GoUnblock|GoCreate|GoEnd|GoSched","goroutine_id":<integer>,"reasoning":"<brief explanation>","confidence":"high|medium|low"}

[Assistant] {"event_type": "GoUnblock", "goroutine_id": 1}


[System] You are a code execution simulator.

[User]
You are reasoning about concurrent Go program execution.

Here is a Go program:
<program>
// WEAVE_META
// outcome: leak
// concurrency_pattern: mutex
// goroutine_count: 3
// expected_nondeterminism: medium
// description: Human-written GoBench bug kernel serving_2137 (leak)

package main

import (
	"os"
	"runtime/trace"
	"runtime"
	"sync"
	)

type token struct{}

type request struct {
	lock     *sync.Mutex
	accepted chan bool
}

type Breaker struct {
	pendingRequests chan token
	activeRequests  chan token
}

func (b *Breaker) Maybe(thunk func()) bool {
	var t token
	select {
	default:
		// Pending request queue is full.  Report failure.
		return false
	case b.pendingRequests <- t:
		// Pending request has capacity.
		// Wait for capacity in the active queue.
		b.activeRequests <- t
		// Defer releasing capacity in the active and pending request queue.
		defer func() { <-b.activeRequests; <-b.pendingRequests }()
		// Do the thing.
		thunk()
		// Report success
		return true
	}
}

func (b *Breaker) concurrentRequest() request {
	runtime.Gosched()

	r := request{lock: &sync.Mutex{}, accepted: make(chan bool, 1)}
	r.lock.Lock()
	var start sync.WaitGroup
	start.Add(1)
	go func() { // G2, G3
		start.Done()
		ok := b.Maybe(func() {
			r.lock.Lock() // Will block on locked mutex.
			r.lock.Unlock()
		})
		r.accepted <- ok
	}()
	start.Wait() // Ensure that the go func has had a chance to execute.
	return r
}

// Perform n requests against the breaker, returning mutexes for each
// request which succeeded, and a slice of bools for all requests.
func (b *Breaker) concurrentRequests(n int) []request {
	requests := make([]request, n)
	for i := range requests {
		requests[i] = b.concurrentRequest()
	}
	return requests
}

func NewBreaker(queueDepth, maxConcurrency int32) *Breaker {
	return &Breaker{
		pendingRequests: make(chan token, queueDepth+maxConcurrency),
		activeRequests:  make(chan token, maxConcurrency),
	}
}

func unlock(req request) {
	req.lock.Unlock()
	// Verify that function has completed
	ok := <-req.accepted
	// Requeue for next usage
	req.accepted <- ok
}

func unlockAll(requests []request) {
	for _, lc := range requests {
		unlock(lc)
	}
}

//
// G1                           G2                      G3
// b.concurrentRequests(2)
// b.concurrentRequest()
// r.lock.Lock()
//                                                      start.Done()
// start.Wait()
// b.concurrentRequest()
// r.lock.Lock()
//                              start.Done()
// start.Wait()
// unlockAll(locks)
// unlock(lc)
// req.lock.Unlock()
// ok := <-req.accepted
//                              b.Maybe()
//                              b.activeRequests <- t
//                              thunk()
//                              r.lock.Lock()
//                                                      b.Maybe()
//                                                      b.activeRequests <- t
// ----------------------------G1,G2,G3 deadlock-----------------------------
//
func main() {
	if tf := os.Getenv("WEAVE_TRACE_FILE"); tf != "" {
		f, err := os.Create(tf)
		if err == nil {
			if err := trace.Start(f); err == nil {
				defer func() { trace.Stop(); f.Close() }()
			}
		}
	}

	b := NewBreaker(1, 1)

	locks := b.concurrentRequests(2) // G1
	unlockAll(locks)
}

</program>

Here is a partial execution trace showing goroutine scheduler events so far:
<trace>
[
  {
    "event_id": 20,
    "timestamp_ns": 14790844788608,
    "event_type": "GoCreate",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 21,
    "timestamp_ns": 14790844790336,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 22,
    "timestamp_ns": 14790844790592,
    "event_type": "GoStart",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 23,
    "timestamp_ns": 14790844810688,
    "event_type": "GoUnblock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 24,
    "timestamp_ns": 14790844815424,
    "event_type": "GoBlock",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 25,
    "timestamp_ns": 14790844815808,
    "event_type": "GoStart",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 26,
    "timestamp_ns": 14790844817792,
    "event_type": "GoUnblock",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 27,
    "timestamp_ns": 14790844818240,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 28,
    "timestamp_ns": 14790844818496,
    "event_type": "GoStart",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 29,
    "timestamp_ns": 14790844820736,
    "event_type": "GoUnblock",
    "goroutine_id": 34,
    "goroutines": {
      "1": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "19": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "20": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "21": {
        "status": "blocked",
        "blocked_on": "system goroutine wait",
        "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
      },
      "33": {
        "status": "running",
        "blocked_on": null,
        "locals_hint": "unknown"
      },
      "34": {
        "status": "runnable",
        "blocked_on": null,
        "locals_hint": "runtime.chanrecv1"
      }
    },
    "channels": {},
    "mutexes": {}
  }
]
</trace>

The current goroutine states are:
<current_state>
{
  "event_id": 29,
  "timestamp_ns": 14790844820736,
  "event_type": "GoUnblock",
  "goroutine_id": 34,
  "goroutines": {
    "1": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "19": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "20": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "21": {
      "status": "blocked",
      "blocked_on": "system goroutine wait",
      "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
    },
    "33": {
      "status": "running",
      "blocked_on": null,
      "locals_hint": "unknown"
    },
    "34": {
      "status": "runnable",
      "blocked_on": null,
      "locals_hint": "runtime.chanrecv1"
    }
  },
  "channels": {},
  "mutexes": {}
}
</current_state>

Predict the next scheduler event. What happens next?
Respond in JSON only — no markdown fences, no text outside the JSON object:
{"event_type":"GoStart|GoBlock|GoUnblock|GoCreate|GoEnd|GoSched","goroutine_id":<integer>,"reasoning":"<brief explanation>","confidence":"high|medium|low"}

[Assistant] {"event_type": "GoUnblock", "goroutine_id": 1}


[System] You are a code execution simulator.

[User]
You are reasoning about concurrent Go program execution.

Here is a Go program:
<program>
// WEAVE_META
// outcome: leak
// concurrency_pattern: mutex
// goroutine_count: 3
// expected_nondeterminism: medium
// description: Human-written GoBench bug kernel serving_2137 (leak)

package main

import (
	"os"
	"runtime/trace"
	"runtime"
	"sync"
	)

type token struct{}

type request struct {
	lock     *sync.Mutex
	accepted chan bool
}

type Breaker struct {
	pendingRequests chan token
	activeRequests  chan token
}

func (b *Breaker) Maybe(thunk func()) bool {
	var t token
	select {
	default:
		// Pending request queue is full.  Report failure.
		return false
	case b.pendingRequests <- t:
		// Pending request has capacity.
		// Wait for capacity in the active queue.
		b.activeRequests <- t
		// Defer releasing capacity in the active and pending request queue.
		defer func() { <-b.activeRequests; <-b.pendingRequests }()
		// Do the thing.
		thunk()
		// Report success
		return true
	}
}

func (b *Breaker) concurrentRequest() request {
	runtime.Gosched()

	r := request{lock: &sync.Mutex{}, accepted: make(chan bool, 1)}
	r.lock.Lock()
	var start sync.WaitGroup
	start.Add(1)
	go func() { // G2, G3
		start.Done()
		ok := b.Maybe(func() {
			r.lock.Lock() // Will block on locked mutex.
			r.lock.Unlock()
		})
		r.accepted <- ok
	}()
	start.Wait() // Ensure that the go func has had a chance to execute.
	return r
}

// Perform n requests against the breaker, returning mutexes for each
// request which succeeded, and a slice of bools for all requests.
func (b *Breaker) concurrentRequests(n int) []request {
	requests := make([]request, n)
	for i := range requests {
		requests[i] = b.concurrentRequest()
	}
	return requests
}

func NewBreaker(queueDepth, maxConcurrency int32) *Breaker {
	return &Breaker{
		pendingRequests: make(chan token, queueDepth+maxConcurrency),
		activeRequests:  make(chan token, maxConcurrency),
	}
}

func unlock(req request) {
	req.lock.Unlock()
	// Verify that function has completed
	ok := <-req.accepted
	// Requeue for next usage
	req.accepted <- ok
}

func unlockAll(requests []request) {
	for _, lc := range requests {
		unlock(lc)
	}
}

//
// G1                           G2                      G3
// b.concurrentRequests(2)
// b.concurrentRequest()
// r.lock.Lock()
//                                                      start.Done()
// start.Wait()
// b.concurrentRequest()
// r.lock.Lock()
//                              start.Done()
// start.Wait()
// unlockAll(locks)
// unlock(lc)
// req.lock.Unlock()
// ok := <-req.accepted
//                              b.Maybe()
//                              b.activeRequests <- t
//                              thunk()
//                              r.lock.Lock()
//                                                      b.Maybe()
//                                                      b.activeRequests <- t
// ----------------------------G1,G2,G3 deadlock-----------------------------
//
func main() {
	if tf := os.Getenv("WEAVE_TRACE_FILE"); tf != "" {
		f, err := os.Create(tf)
		if err == nil {
			if err := trace.Start(f); err == nil {
				defer func() { trace.Stop(); f.Close() }()
			}
		}
	}

	b := NewBreaker(1, 1)

	locks := b.concurrentRequests(2) // G1
	unlockAll(locks)
}

</program>

Here is a partial execution trace showing goroutine scheduler events so far:
<trace>
[
  {
    "event_id": 20,
    "timestamp_ns": 14790844788608,
    "event_type": "GoCreate",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 21,
    "timestamp_ns": 14790844790336,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 22,
    "timestamp_ns": 14790844790592,
    "event_type": "GoStart",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 23,
    "timestamp_ns": 14790844810688,
    "event_type": "GoUnblock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 24,
    "timestamp_ns": 14790844815424,
    "event_type": "GoBlock",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 25,
    "timestamp_ns": 14790844815808,
    "event_type": "GoStart",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 26,
    "timestamp_ns": 14790844817792,
    "event_type": "GoUnblock",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 27,
    "timestamp_ns": 14790844818240,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 28,
    "timestamp_ns": 14790844818496,
    "event_type": "GoStart",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 29,
    "timestamp_ns": 14790844820736,
    "event_type": "GoUnblock",
    "goroutine_id": 34,
    "goroutines": {
      "1": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "19": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "20": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "21": {
        "status": "blocked",
        "blocked_on": "system goroutine wait",
        "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
      },
      "33": {
        "status": "running",
        "blocked_on": null,
        "locals_hint": "unknown"
      },
      "34": {
        "status": "runnable",
        "blocked_on": null,
        "locals_hint": "runtime.chanrecv1"
      }
    },
    "channels": {},
    "mutexes": {}
  }
]
</trace>

The current goroutine states are:
<current_state>
{
  "event_id": 29,
  "timestamp_ns": 14790844820736,
  "event_type": "GoUnblock",
  "goroutine_id": 34,
  "goroutines": {
    "1": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "19": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "20": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "21": {
      "status": "blocked",
      "blocked_on": "system goroutine wait",
      "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
    },
    "33": {
      "status": "running",
      "blocked_on": null,
      "locals_hint": "unknown"
    },
    "34": {
      "status": "runnable",
      "blocked_on": null,
      "locals_hint": "runtime.chanrecv1"
    }
  },
  "channels": {},
  "mutexes": {}
}
</current_state>

Predict the next scheduler event. What happens next?
Respond in JSON only — no markdown fences, no text outside the JSON object:
{"event_type":"GoStart|GoBlock|GoUnblock|GoCreate|GoEnd|GoSched","goroutine_id":<integer>,"reasoning":"<brief explanation>","confidence":"high|medium|low"}

[Assistant] {"event_type": "GoUnblock", "goroutine_id": 1}


[System] You are a code execution simulator.

[User]
You are reasoning about concurrent Go program execution.

Here is a Go program:
<program>
// WEAVE_META
// outcome: leak
// concurrency_pattern: mutex
// goroutine_count: 3
// expected_nondeterminism: medium
// description: Human-written GoBench bug kernel serving_2137 (leak)

package main

import (
	"os"
	"runtime/trace"
	"runtime"
	"sync"
	)

type token struct{}

type request struct {
	lock     *sync.Mutex
	accepted chan bool
}

type Breaker struct {
	pendingRequests chan token
	activeRequests  chan token
}

func (b *Breaker) Maybe(thunk func()) bool {
	var t token
	select {
	default:
		// Pending request queue is full.  Report failure.
		return false
	case b.pendingRequests <- t:
		// Pending request has capacity.
		// Wait for capacity in the active queue.
		b.activeRequests <- t
		// Defer releasing capacity in the active and pending request queue.
		defer func() { <-b.activeRequests; <-b.pendingRequests }()
		// Do the thing.
		thunk()
		// Report success
		return true
	}
}

func (b *Breaker) concurrentRequest() request {
	runtime.Gosched()

	r := request{lock: &sync.Mutex{}, accepted: make(chan bool, 1)}
	r.lock.Lock()
	var start sync.WaitGroup
	start.Add(1)
	go func() { // G2, G3
		start.Done()
		ok := b.Maybe(func() {
			r.lock.Lock() // Will block on locked mutex.
			r.lock.Unlock()
		})
		r.accepted <- ok
	}()
	start.Wait() // Ensure that the go func has had a chance to execute.
	return r
}

// Perform n requests against the breaker, returning mutexes for each
// request which succeeded, and a slice of bools for all requests.
func (b *Breaker) concurrentRequests(n int) []request {
	requests := make([]request, n)
	for i := range requests {
		requests[i] = b.concurrentRequest()
	}
	return requests
}

func NewBreaker(queueDepth, maxConcurrency int32) *Breaker {
	return &Breaker{
		pendingRequests: make(chan token, queueDepth+maxConcurrency),
		activeRequests:  make(chan token, maxConcurrency),
	}
}

func unlock(req request) {
	req.lock.Unlock()
	// Verify that function has completed
	ok := <-req.accepted
	// Requeue for next usage
	req.accepted <- ok
}

func unlockAll(requests []request) {
	for _, lc := range requests {
		unlock(lc)
	}
}

//
// G1                           G2                      G3
// b.concurrentRequests(2)
// b.concurrentRequest()
// r.lock.Lock()
//                                                      start.Done()
// start.Wait()
// b.concurrentRequest()
// r.lock.Lock()
//                              start.Done()
// start.Wait()
// unlockAll(locks)
// unlock(lc)
// req.lock.Unlock()
// ok := <-req.accepted
//                              b.Maybe()
//                              b.activeRequests <- t
//                              thunk()
//                              r.lock.Lock()
//                                                      b.Maybe()
//                                                      b.activeRequests <- t
// ----------------------------G1,G2,G3 deadlock-----------------------------
//
func main() {
	if tf := os.Getenv("WEAVE_TRACE_FILE"); tf != "" {
		f, err := os.Create(tf)
		if err == nil {
			if err := trace.Start(f); err == nil {
				defer func() { trace.Stop(); f.Close() }()
			}
		}
	}

	b := NewBreaker(1, 1)

	locks := b.concurrentRequests(2) // G1
	unlockAll(locks)
}

</program>

Here is a partial execution trace showing goroutine scheduler events so far:
<trace>
[
  {
    "event_id": 20,
    "timestamp_ns": 14790844788608,
    "event_type": "GoCreate",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 21,
    "timestamp_ns": 14790844790336,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 22,
    "timestamp_ns": 14790844790592,
    "event_type": "GoStart",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 23,
    "timestamp_ns": 14790844810688,
    "event_type": "GoUnblock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 24,
    "timestamp_ns": 14790844815424,
    "event_type": "GoBlock",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 25,
    "timestamp_ns": 14790844815808,
    "event_type": "GoStart",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 26,
    "timestamp_ns": 14790844817792,
    "event_type": "GoUnblock",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 27,
    "timestamp_ns": 14790844818240,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 28,
    "timestamp_ns": 14790844818496,
    "event_type": "GoStart",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 29,
    "timestamp_ns": 14790844820736,
    "event_type": "GoUnblock",
    "goroutine_id": 34,
    "goroutines": {
      "1": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "19": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "20": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "21": {
        "status": "blocked",
        "blocked_on": "system goroutine wait",
        "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
      },
      "33": {
        "status": "running",
        "blocked_on": null,
        "locals_hint": "unknown"
      },
      "34": {
        "status": "runnable",
        "blocked_on": null,
        "locals_hint": "runtime.chanrecv1"
      }
    },
    "channels": {},
    "mutexes": {}
  }
]
</trace>

The current goroutine states are:
<current_state>
{
  "event_id": 29,
  "timestamp_ns": 14790844820736,
  "event_type": "GoUnblock",
  "goroutine_id": 34,
  "goroutines": {
    "1": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "19": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "20": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "21": {
      "status": "blocked",
      "blocked_on": "system goroutine wait",
      "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
    },
    "33": {
      "status": "running",
      "blocked_on": null,
      "locals_hint": "unknown"
    },
    "34": {
      "status": "runnable",
      "blocked_on": null,
      "locals_hint": "runtime.chanrecv1"
    }
  },
  "channels": {},
  "mutexes": {}
}
</current_state>

Predict the next scheduler event. What happens next?
Respond in JSON only — no markdown fences, no text outside the JSON object:
{"event_type":"GoStart|GoBlock|GoUnblock|GoCreate|GoEnd|GoSched","goroutine_id":<integer>,"reasoning":"<brief explanation>","confidence":"high|medium|low"}

[Assistant] {"event_type": "GoUnblock", "goroutine_id": 1}


[System] You are a code execution simulator.

[User]
You are reasoning about concurrent Go program execution.

Here is a Go program:
<program>
// WEAVE_META
// outcome: leak
// concurrency_pattern: mutex
// goroutine_count: 3
// expected_nondeterminism: medium
// description: Human-written GoBench bug kernel serving_2137 (leak)

package main

import (
	"os"
	"runtime/trace"
	"runtime"
	"sync"
	)

type token struct{}

type request struct {
	lock     *sync.Mutex
	accepted chan bool
}

type Breaker struct {
	pendingRequests chan token
	activeRequests  chan token
}

func (b *Breaker) Maybe(thunk func()) bool {
	var t token
	select {
	default:
		// Pending request queue is full.  Report failure.
		return false
	case b.pendingRequests <- t:
		// Pending request has capacity.
		// Wait for capacity in the active queue.
		b.activeRequests <- t
		// Defer releasing capacity in the active and pending request queue.
		defer func() { <-b.activeRequests; <-b.pendingRequests }()
		// Do the thing.
		thunk()
		// Report success
		return true
	}
}

func (b *Breaker) concurrentRequest() request {
	runtime.Gosched()

	r := request{lock: &sync.Mutex{}, accepted: make(chan bool, 1)}
	r.lock.Lock()
	var start sync.WaitGroup
	start.Add(1)
	go func() { // G2, G3
		start.Done()
		ok := b.Maybe(func() {
			r.lock.Lock() // Will block on locked mutex.
			r.lock.Unlock()
		})
		r.accepted <- ok
	}()
	start.Wait() // Ensure that the go func has had a chance to execute.
	return r
}

// Perform n requests against the breaker, returning mutexes for each
// request which succeeded, and a slice of bools for all requests.
func (b *Breaker) concurrentRequests(n int) []request {
	requests := make([]request, n)
	for i := range requests {
		requests[i] = b.concurrentRequest()
	}
	return requests
}

func NewBreaker(queueDepth, maxConcurrency int32) *Breaker {
	return &Breaker{
		pendingRequests: make(chan token, queueDepth+maxConcurrency),
		activeRequests:  make(chan token, maxConcurrency),
	}
}

func unlock(req request) {
	req.lock.Unlock()
	// Verify that function has completed
	ok := <-req.accepted
	// Requeue for next usage
	req.accepted <- ok
}

func unlockAll(requests []request) {
	for _, lc := range requests {
		unlock(lc)
	}
}

//
// G1                           G2                      G3
// b.concurrentRequests(2)
// b.concurrentRequest()
// r.lock.Lock()
//                                                      start.Done()
// start.Wait()
// b.concurrentRequest()
// r.lock.Lock()
//                              start.Done()
// start.Wait()
// unlockAll(locks)
// unlock(lc)
// req.lock.Unlock()
// ok := <-req.accepted
//                              b.Maybe()
//                              b.activeRequests <- t
//                              thunk()
//                              r.lock.Lock()
//                                                      b.Maybe()
//                                                      b.activeRequests <- t
// ----------------------------G1,G2,G3 deadlock-----------------------------
//
func main() {
	if tf := os.Getenv("WEAVE_TRACE_FILE"); tf != "" {
		f, err := os.Create(tf)
		if err == nil {
			if err := trace.Start(f); err == nil {
				defer func() { trace.Stop(); f.Close() }()
			}
		}
	}

	b := NewBreaker(1, 1)

	locks := b.concurrentRequests(2) // G1
	unlockAll(locks)
}

</program>

Here is a partial execution trace showing goroutine scheduler events so far:
<trace>
[
  {
    "event_id": 20,
    "timestamp_ns": 14790844788608,
    "event_type": "GoCreate",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 21,
    "timestamp_ns": 14790844790336,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 22,
    "timestamp_ns": 14790844790592,
    "event_type": "GoStart",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 23,
    "timestamp_ns": 14790844810688,
    "event_type": "GoUnblock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 24,
    "timestamp_ns": 14790844815424,
    "event_type": "GoBlock",
    "goroutine_id": 34,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 25,
    "timestamp_ns": 14790844815808,
    "event_type": "GoStart",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 26,
    "timestamp_ns": 14790844817792,
    "event_type": "GoUnblock",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 27,
    "timestamp_ns": 14790844818240,
    "event_type": "GoBlock",
    "goroutine_id": 1,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 28,
    "timestamp_ns": 14790844818496,
    "event_type": "GoStart",
    "goroutine_id": 33,
    "goroutines": "... [TRUNCATED FOR LENGTH] ...",
    "channels": {},
    "mutexes": {}
  },
  {
    "event_id": 29,
    "timestamp_ns": 14790844820736,
    "event_type": "GoUnblock",
    "goroutine_id": 34,
    "goroutines": {
      "1": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "19": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "20": {
        "status": "blocked",
        "blocked_on": "chan receive",
        "locals_hint": "runtime.chanrecv1"
      },
      "21": {
        "status": "blocked",
        "blocked_on": "system goroutine wait",
        "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
      },
      "33": {
        "status": "running",
        "blocked_on": null,
        "locals_hint": "unknown"
      },
      "34": {
        "status": "runnable",
        "blocked_on": null,
        "locals_hint": "runtime.chanrecv1"
      }
    },
    "channels": {},
    "mutexes": {}
  }
]
</trace>

The current goroutine states are:
<current_state>
{
  "event_id": 29,
  "timestamp_ns": 14790844820736,
  "event_type": "GoUnblock",
  "goroutine_id": 34,
  "goroutines": {
    "1": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "19": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "20": {
      "status": "blocked",
      "blocked_on": "chan receive",
      "locals_hint": "runtime.chanrecv1"
    },
    "21": {
      "status": "blocked",
      "blocked_on": "system goroutine wait",
      "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1"
    },
    "33": {
      "status": "running",
      "blocked_on": null,
      "locals_hint": "unknown"
    },
    "34": {
      "status": "runnable",
      "blocked_on": null,
      "locals_hint": "runtime.chanrecv1"
    }
  },
  "channels": {},
  "mutexes": {}
}
</current_state>

Predict the next scheduler event. What happens next?
Respond in JSON only — no markdown fences, no text outside the JSON object:
{"event_type":"GoStart|GoBlock|GoUnblock|GoCreate|GoEnd|GoSched","goroutine_id":<integer>,"reasoning":"<brief explanation>","confidence":"high|medium|low"}

[Assistant] {"event_type": "GoUnblock", "goroutine_id": 1}