## Stack Context
This stack makes AI Gateway data and budgets the source of truth for AI
spend controls.
1. Re-back the per-chat cost endpoint with AI Gateway data (#27328,
merged).
2. **This PR:** remove native chat usage limits.
3. Remove native chat cost tracking and its dedicated admin UI (#27330).
## Summary
Removes the native usage-limit API, SDK types, SQL, and chat enforcement
for deployment, user, and group chat limits. Compact AI Gateway budget
indicators remain in the Agents sidebar, user menu, and group settings.
Gateway budget rejections and provider quota failures continue to
classify as usage-limit errors, including a 409 response for synchronous
title generation.
Budget-period labels now use the API's UTC boundaries, so users see the
same dates in every browser timezone. The documentation explains the AI
Gateway replacement, its licensing requirements, and the differences
from native limits.
No schema is dropped in this release. The usage-limit table, index, user
and group columns, constraints, audit mappings, and generated scan
fields remain for mixed-version rolling upgrades. #27600 tracks their
removal after the compatibility window.
## Breaking change
Native day, week, and month chat spend limits are removed and are not
migrated. AI Gateway budgets are month-based, group-scoped with per-user
overrides, and require the AI Gateway entitlement. Deployments without
that entitlement no longer have chat spend enforcement.
> Mux prepared this PR on Mike's behalf.
Blocked turns from a provider's content filter (Anthropic's `refusal`
stop reason with empty content) previously ended silently on the
"Thinking" spinner. They now end as a terminal `content_filter` error
that renders as a "Response blocked" message with the provider's
category and explanation.
<img width="888" height="335" alt="image"
src="https://github.com/user-attachments/assets/cef85a59-4091-4e62-9d45-1eb06748db48"
/>
Closes CODAGT-611
Follow-ups will involve implementing fallbacks, but this alone is pretty
important
Renames the Agents chat stream-silence error from `startup_timeout` to
`stream_silence_timeout` now that the timeout applies to any gap between
provider stream parts, not just first-token startup.
Updates the SDK enum, generated API docs/types, chat error copy, and
Agents UI stories/status labels so the user-facing wording describes a
stalled provider response instead of startup delay.
> **Breaking change:** This is a very minor breaking change for the
Coder Agents API: the public chat error kind enum no longer includes
`startup_timeout`, so clients matching that specific value should handle
`stream_silence_timeout` instead.
Builds on top of https://github.com/coder/coder/pull/25794
Adds a new `provider_disabled` error classification in `chatd` with the
corresponding plumbing to classify it as non-retryable. Also adds a
story for how this particular error kind is displayed in the UI.
Fixes CODAGT-484.
- Removed "quota", "billing", "insufficient_quota", "payment required"
from `authStrongPatterns`
- Added `usageLimitPatterns` slice with those patterns
- Added `usageLimitMatch` signal and rule between overloaded and
authStrong in priority
- Added terminal/retry messages for `ChatErrorKindUsageLimit`
- Simplified auth message (removed billing reference)
- Frontend: conditional `!usageLimitStatus.provider` guard on the "View
Usage" Alert
- Added `TestClassify_UsageLimitBeatsAuth` with 5 cases including real
production OpenAI error
- Added `ProviderQuotaExceeded` story asserting no "View Usage" link and
correct `ChatStatusCallout` rendering
> Generated with [Coder Agents](https://coder.com/agents)
coder/fantasy now fails closed when Anthropic or OpenAI Responses
streams close before their provider terminal events instead of yielding
a successful finish.
This bumps the fantasy replacement to coder/fantasy#33 and teaches chat
error classification to treat those failures as retryable timeout errors
with explicit stream-closed messages.
<img width="875" height="311" alt="image"
src="https://github.com/user-attachments/assets/69c6f7b5-c885-46d2-a88b-b7a2b111bd55"
/>
Moves the chat error kind taxonomy from `coderd/x/chatd/chaterror` into
`codersdk.ChatErrorKind` and types `ChatError.Kind` /
`ChatStreamRetry.Kind` so generated TypeScript exposes an SDK-owned
union, including `usage_limit`. Backend chat classification now
references the SDK constants directly while preserving the existing JSON
string values.
Keeps chat usage-limit admission failures on their existing 409 response
shape. The frontend maps structured usage-limit responses to the
SDK-owned `usage_limit` kind, uses generated `TypesGen.ChatErrorKind`
directly, and removes the local string union and alias.
**Breaking change for changelog:**
> `codersdk.Chat.last_error` now returns a structured `ChatError` object
(`{message, kind, provider, retryable, status_code, detail}`) instead of
a plain string. The chats API is experimental
(`/api/experimental/chats`), so this ships without a deprecation cycle;
consumers reading `chat.last_error` as a string must update to read
`chat.last_error.message`. SDK/generated TypeScript terminal error
payloads now use the single `ChatError` type; the live stream error
payload type is renamed from `ChatStreamError` to `ChatError`.
Persisted chat errors now carry the same provider-specific detail (kind,
provider, retryable, HTTP status, optional detail) as the live stream,
so refreshing a failed chat rehydrates with the full structured error
instead of a one-line headline.
Existing rows are migrated in place: legacy text errors are wrapped into
`{message, kind: "generic"}` so already-errored chats still render, and
rows with `last_error IS NULL` stay NULL. Internally, persisted fallback
decoding now reuses the existing `chaterror.KindGeneric` constant, with
no JSON value change.
Closes CODAGT-239
Follow-up to #23282. The retry and terminal error callouts had a few UX
oddities:
- Auto-retrying states reused backend error text that said "Please try
again" even while the UI was already retrying on behalf of the user.
- Terminal error states also said "Please try again" with no action the
user could take.
- `startup_timeout` had no specific title or retry copy — it fell
through to the generic "Retrying request" heading.
- The kind pill showed raw enum values like `startup_timeout` and
`rate_limit`.
- Terminal error metadata showed a "Retryable" / "Not retryable" label
that does not help users.
- A separate "Provider anthropic" metadata row duplicated information
already present in the message body.
- The `usage-limit` error kind used a hyphen while every backend kind
uses underscores.
Changes:
**Backend (`chaterror/message.go`)**
- Split message generation into `terminalMessage()` and
`retryMessage()`, replacing the old `userFacingMessage()`.
- Terminal messages include HTTP status codes and actionable guidance
(e.g. "Check the API key, permissions, and billing settings.").
- Retry messages are clean factual statements without status codes or
remediation, suitable for the retry countdown UI (e.g. "Anthropic is
temporarily overloaded.").
- Removed "Please try again" / "Please try again later" from all paths.
- `StreamRetryPayload` calls `retryMessage()` instead of forwarding
`classified.Message`.
**Frontend**
- Removed the parallel frontend message-generation system:
`getRetryMessage()`, `getProviderDisplayName()`,
`getRetryProviderSubject()`, and the `PROVIDER_DISPLAY_NAMES` map are
all deleted from `chatStatusHelpers.ts`.
- `liveStatusModel.ts` passes `retryState.error` through directly — the
backend owns the copy.
- Added specific title and retry copy for `startup_timeout`, and
extended the title mapping to cover `auth` and `config`.
- Kind pills now show humanized labels ("Startup timeout", "Rate limit",
etc.) instead of raw enum strings.
- Removed the redundant "Provider anthropic" metadata row.
- Removed the terminal "Retryable" / "Not retryable" badge.
- Normalized `"usage-limit"` → `"usage_limit"` and added it to
`ChatProviderFailureKind` so all error kinds follow the same underscore
convention and live in one enum.
Refs #23282.
> **PR Stack**
> 1. #23351 ← `#23282`
> 2. #23282 ← `#23275`
> 3. **#23275** ← `#23349` *(you are here)*
> 4. #23349 ← `main`
---
## Summary
Extracts a structured error classification subsystem for agent chat
(`chatd`) so that retry and error payloads carry machine-readable
metadata — error kind, provider name, HTTP status code, and retryability
— instead of raw error strings.
This is the **backend half** of the error-handling work. The frontend
counterpart is in #23282.
## Changes
### New package: `coderd/chatd/chaterror/`
Canonical error classification — extracts error kind, provider, status
code, and user-facing message from raw provider errors. One source of
truth that drives both retry policy and stream payloads.
- **`kind.go`**: Error kind enum (`rate_limit`, `timeout`, `auth`,
`config`, `overloaded`, `unknown`).
- **`signals.go`**: Signal extraction — parses provider name, HTTP
status code, and retryability from error strings and wrapped types.
- **`classify.go`**: Classification logic — maps extracted signals to an
error kind.
- **`message.go`**: User-facing message templates keyed by kind +
signals.
- **`payload.go`**: Projectors that build `ChatStreamError` and
`ChatStreamRetry` payloads from a classified error.
### Modified
- **`codersdk/chats.go`**: Added `Kind`, `Provider`, `Retryable`,
`StatusCode` fields to `ChatStreamError` and `ChatStreamRetry`.
- **`coderd/chatd/chatretry/`**: Thinned to retry-policy only;
classification logic moved to `chaterror`.
- **`coderd/chatd/chatloop/`**: Added per-attempt first-chunk timeout
(60 s) via `guardedStream` wrapper — produces retryable
`startup_timeout` errors instead of hanging forever.
- **`coderd/chatd/chatd.go`**: Publishes normalized retry/error payloads
via `chaterror` projectors.
Michael Suchacz