title: Subagent forked context

scenario:
  id: subagent-forked-context
  surface: subagents
  coverage:
    primary:
      - agents.subagents
  objective: Verify the agent can choose forked subagent context when the child needs the current transcript.
  successCriteria:
    - Agent launches a native subagent with context=fork.
    - Subagent uses the forked requester transcript to recover the visible code.
    - Subagent request remains bounded and does not switch to ACP.
    - User-visible output includes the delegated result and the visible code.
  docsRefs:
    - docs/tools/subagents.md
    - docs/concepts/session-tool.md
  codeRefs:
    - src/agents/tools/sessions-spawn-tool.ts
    - src/agents/subagent-spawn.ts
  execution:
    kind: flow
    summary: Ask the agent to delegate work that depends on the current transcript and assert sessions_spawn carries context=fork.
    config:
      requiredChannelDriver: qa-channel
      contextNeedle: FORKED-CONTEXT-ALPHA
      prompt: "Forked subagent context QA check. The visible code in this current conversation is FORKED-CONTEXT-ALPHA. Delegate to a native subagent to report the visible code from the requester transcript. Do not include the visible code in the child task text; the child must recover it from forked transcript context. Use forked context if the child needs the current transcript; otherwise it will not know the code. A spawn-accepted result is not the answer. Wait for the child completion, then make sure user-visible output includes the visible code."

flow:
  steps:
    - name: forks current transcript context for the child
      actions:
        - call: reset
        - call: runAgentPrompt
          args:
            - ref: env
            - sessionKey: agent:qa:forked-context
              message:
                expr: config.prompt
              timeoutMs:
                expr: liveTurnTimeoutMs(env, 90000)
        - call: waitForCondition
          saveAs: outbound
          args:
            - lambda:
                expr: "state.getSnapshot().messages.filter((candidate) => candidate.direction === 'outbound' && candidate.conversation.id === 'qa-operator' && String(candidate.text ?? '').includes(config.contextNeedle) && !normalizeLowercaseStringOrEmpty(candidate.text).includes('waiting')).at(-1)"
            - expr: liveTurnTimeoutMs(env, 45000)
            - expr: "env.providerMode === 'mock-openai' ? 100 : 250"
        - assert:
            expr: "env.mock || String(outbound.text ?? '').includes(config.contextNeedle)"
            message:
              expr: "`expected live final answer to include fork-only context code ${config.contextNeedle}, got: ${outbound.text}`"
        - set: forkDebugRequests
          value:
            expr: "env.mock ? [...(await fetchJson(`${env.mock.baseUrl}/debug/requests`))] : []"
        - assert:
            expr: "!env.mock || forkDebugRequests.some((request) => !request.toolOutput && /forked subagent context qa check/i.test(String(request.allInputText ?? '')) && request.plannedToolName === 'sessions_spawn' && (request.plannedToolArgs?.context === 'fork' || /context\\s*=\\s*fork/i.test(String(request.allInputText ?? ''))))"
            message:
              expr: "`expected sessions_spawn context=fork during forked context scenario, saw ${JSON.stringify(forkDebugRequests.map((request) => ({ plannedToolName: request.plannedToolName ?? null, plannedToolArgs: request.plannedToolArgs ?? null })))} `"
      detailsExpr: outbound.text