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
Two documentation improvements for the AI chat docs.
**Head-start persistence contract.** The fast starts page now documents
what your hooks can rely on across a head-start handover: one stable
assistant `messageId` for the whole turn, `onTurnComplete` as the
canonical persistence point, reasoning parts flowing into durable
history, and how Head Start composes with `hydrateMessages` (the
first-turn history arrives as `incomingMessages`, and the runtime
splices the warm partial onto the hydrated chain, deduplicated by id).
The hydrate examples on the lifecycle hooks and database persistence
pages now upsert their conversation row, since head-start first turns
run without a preload to create it.
**Sessions page.** The page opened with "a durable, task-bound,
bi-directional I/O channel pair", which reads as jargon and omitted run
orchestration entirely. It now leads with the plain mental model (a pair
of durable streams: input carries user messages, output carries
everything the agent produces) plus the Session's role orchestrating
runs, a diagram, a minimal runnable example, and a section on the
one-session-many-runs lifecycle.
Documents behavior shipping in
[#3907](https://github.com/triggerdotdev/trigger.dev/pull/3907).
## Summary
A new guide for connecting a database to your tasks: where to create the
client, how to size the connection pool against your provider's limit,
when to reach for a pooler, and how to release connections at waits so
you don't hit "too many connections" or crash on resume.
It covers node-postgres, Prisma, Drizzle, and MongoDB, with researched
direct and pooled connection limits for the common Postgres providers
(Supabase, Neon, RDS, PlanetScale) and MongoDB Atlas. The page lives
under Documentation, Troubleshooting, and is linked from the chat agent
docs (overview, lifecycle hooks, chat.local, and the database
persistence pattern).
## Summary
Updates the AI chat docs to match the slim-wire + field-level merge
behavior shipped in #3719 and the precise `.in/append` cap +
CORS-readable 413 shipped in #3720. No behavior changes here — code is
correct in `main`; the docs were lagging on three patterns customers
copy out of the page.
## What changed
- **`hydrateMessages` examples upsert by id** (in `lifecycle-hooks.mdx`,
`patterns/database-persistence.mdx`, and
`patterns/persistence-and-replay.mdx`). The previous
`stored.push(newMsg)` pattern duplicated the assistant id on HITL
continuations and caused the LLM to receive a tool call with no
`arguments`. The new examples include the rationale inline.
- **`onValidateMessages` example filters to user messages**
(`lifecycle-hooks.mdx`). The previous example called
`validateUIMessages({ messages, tools })` directly, which now throws on
HITL slim wires (the AI SDK schema requires `input` on resolved tool
parts). New example shows the filter pattern, with a Warning callout
explaining why.
- **Merge contract description updated** (`lifecycle-hooks.mdx`). The
old wording said incoming messages are "auto-merged" / "replaced"; the
new description explains the actual field-level overlay (state advances
only).
- **Approval-responded wire example slimmed** (`client-protocol.mdx`).
Shows the minimum shape the agent reads — `state` + `approval` (or
`output` / `errorText` for HITL). Notes that the built-in transports
ship this slim shape by default and that fuller shapes are still
accepted.
- **`/in/append` 413 row and FAQ updated** (`client-protocol.mdx`,
`patterns/trusted-edge-signals.mdx`). Reflects the new precise S2 cap
and the CORS-readable 413.
- **New changelog entry** at the top of `changelog.mdx` covering all of
the above.
The historical `## 512 KiB ceiling removed` entry further down the
changelog is left as-is (it's a snapshot of the prior transition), and
the v4.5 upgrade-guide section is skipped — the merge contract is
backwards compatible.
## Test plan
- Mintlify dev preview renders cleanly with no broken anchors
- Linked references resolve (`/ai-chat/lifecycle-hooks#hydratemessages`,
`/ai-chat/lifecycle-hooks#onvalidatemessages`,
`/ai-chat/patterns/database-persistence#alternative-hydratemessages`,
`/ai-chat/client-protocol#step-3-send-messages-stops-and-actions`,
`/ai-chat/patterns/large-payloads`)
## Summary
Three post-merge fixes for the AI Agents docs (#3226), all caught by
review after merge.
## Fixes
- **`onTurnComplete` examples now use `db.$transaction`** — both the
Database persistence "Complete example" and the Lifecycle hooks
reference example were doing two separate `await` calls
(`db.chat.update` then `db.chatSession.upsert`). That's the exact
non-atomic pattern the warning earlier on the persistence page calls out
as ❌: a refresh between the two writes reads a stale `lastEventId` and
duplicates the assistant message on resume. Both examples now use the
recommended atomic form.
- **Background injection self-review prose aligned with the code** — the
prose said "gpt-4o-mini" but the example above it had been swapped to
`claude-haiku-4-5`. The Anthropic-sweep script only touched code blocks;
this prose line wasn't picked up.
## Test plan
- [x] Both updated examples use `db.$transaction([...])`
- [x] Prose matches the model used in the code block
- [ ] Mintlify deployment passes
## 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)`.
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Eric Allam