TEST-201 docs: bring Simulations pages up to date with Composer test generation and the run API

[scott-lowe-vapi]

Description

Linear: TEST-201. Companion in-repo docs: VapiAI/vapi#23428.

• Composer
  • New section Generate tests for an assistant (/composer#generate-tests-for-an-assistant): requirements draft → Generate coverage → suite card with mocked tools and not-tested gaps → Run suite, plus edits and a tip to run five or more iterations.
  • Limitations: "Cannot test your agent" is replaced by "Cannot test every behavior".
  • Safety › Deletion no longer claims Composer can delete resources. It has no delete tools; only discard-draft, for your own unpublished draft.
• Advanced
  • "Mock tool responses" (anchor unchanged) says generated suites come pre-mocked and explains how to review those mocks.
  • New sections: "Handoffs and transfers in simulations", covering the static-handoff refusal and dynamic handoffs, with a gaps table; and "Hooks and call endings", covering the removed customer.speech.timeout and the tester hang-up ending as customer-ended-call.
  • Four troubleshooting rows.
• Manage (API tabs)
  • The Idempotency-Key header on POST /eval/simulation/run.
  • Run, item and suite filters (suiteId, targetType, targetId, status, simulationId, assistantId, squadId, name).
  • A note that any query parameter switches these lists to { metadata, results }.
• Quickstart: the unmocked-tools warning now applies to hand-built suites only.
• Best practices / Run and maintain: one iteration while setting up, then five or more before trusting a pass rate.
• Overview, Manage, Voice testing: the handoff mentions link to the new limits section.

Evidence

Every behavior was checked against VapiAI/vapi main:

• Dashboard labels: features/simulationsOnboarding/constants.ts.
• Idempotency: simulationRunIdempotencyKeyParse.ts and simulationRunIdempotentReplayGet.ts.
• Filters: simulationRun.types.ts and GetSimulationSuitesDTO.ts.
• Handoffs and hooks: handoffSimulationRefusalGet.ts and simulationTargetReengagementHooks/.

Testing Steps

• fern check (5.151.1) passes: 0 errors. The 14 warnings were already on main.
• Check the preview deployment for the changed pages

[lightsage-app]

Lightsage docs evals

Lightsage could not queue docs evals for this PR.

Docs URL: https://vapi-preview-01a1527c-c7e7-742f-bb13-ed300ead57a9.docs.buildwithfern.com
Commit: d16141f
Reason: No evals are selected for GitHub PR evals. Open Lightsage and enable the GitHub checkbox for at least one eval.

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[scott-lowe-vapi]

• TEST-201 docs: bring Simulations pages up to date with Composer test generation and the run API #1342 : 2 dependent PRs (#1343 , #1344 ) 👈 (View in Graphite)
• main

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