## Summary
Adds a docs page for LLM observability: every opted-in Vercel AI SDK
call inside a task becomes its own span in the run trace, carrying the
model, provider, token counts, cost, and latency. The page covers
turning it on per call with `experimental_telemetry: { isEnabled: true
}`, what each span inspector tab shows (Overview, Messages, Tools, and a
Prompt tab when linked), linking a call to its prompt version with
`toAISDKTelemetry()`, and querying usage across runs with TRQL against
the `llm_metrics` table.
It sits in the AI dropdown under Features, next to
[Prompts](https://trigger.dev/docs/ai/prompts), and cross-links the
[Query](https://trigger.dev/docs/observability/query) page.
It is explicit that capture is opt-in per call (not automatic) and only
covers Vercel AI SDK calls, and notes the `@ai-sdk/otel` requirement on
AI SDK 7. Every API name, span tab, and TRQL column was checked against
the SDK and the live query schema.
## Also in this PR
Corrects one bullet in the [AI Agents
overview](https://trigger.dev/docs/ai-chat/overview): it claimed an
in-progress chat resumes on the new version after a redeploy, which
contradicts the version-upgrades and backend pages. Chat agent runs are
pinned to the version they started on; moving onto new code is an
explicit version upgrade.
Removes the release-candidate framing from the docs for the 4.5 GA: the
`@rc` install caveats on the `skills` CLI command, and the AI Agents and
Prompts release-candidate banner (a shared snippet used across the
ai-chat and prompts pages) plus the `>=4.5.0-rc.0` compatibility pin in
the AI reference.
## Summary
Lands the full AI Agents documentation surface alongside the v4.5
release candidate of `@trigger.dev/sdk`. Covers `chat.agent` end to end
— defining agents, lifecycle hooks, the frontend transport, sub-agents,
recovery from cancel/crash/OOM, AI Prompts integration — and the
Sessions primitive that backs it.
## Coverage
- **Conceptual**: Overview, Quick Start, How it works.
- **Building agents**: Backend (`chat.agent` / `chat.createSession` /
raw primitives), Lifecycle hooks, Frontend transport, Server-side
`AgentChat`, Sessions reference, `chat.local` state primitive,
TypeScript types.
- **Features**: AI Prompts integration, Fast starts (Preload + Head
Start), Compaction, Pending Messages (steering), Background Injection
(`chat.inject` + `chat.defer`), Actions (undo / regenerate / edit),
Error handling.
- **Patterns (13)**: Sub-agents, Branching conversations, Code sandbox,
Database persistence, Persistence and replay, HITL, Tool result
auditing, Large payloads, Agent skills, OOM resilience, Recovery boot,
Trusted edge signals, Version upgrades.
- **Reference**: API Reference, Client Protocol (wire format), Testing
harness (`mockChatAgent`), MCP server tools, Upgrade guide, Changelog.
## Structure changes
- Top-level nav: AI → **Agents**, with sub-groups for *Building agents /
Features / Patterns / Reference*.
- New RC banner snippet on every page links to the supported AI SDK
versions table on the API Reference.
- All examples use Anthropic with `stopWhen: stepCountIs(15)`.
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Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
DKP