## What
Adds provider-native web search tools to the chat system. Anthropic,
OpenAI, and Google all offer server-side web search — this wires them up
as opt-in per-model config options using the existing
`ChatModelProviderOptions` JSONB column (no migration).
Web search is **off by default**.
## Config
Set `web_search_enabled: true` in the model config provider options:
```json
{
"provider_options": {
"anthropic": {
"web_search_enabled": true,
"allowed_domains": ["docs.coder.com", "github.com"]
}
}
}
```
Available options per provider:
- **Anthropic**: `web_search_enabled`, `allowed_domains`,
`blocked_domains`
- **OpenAI**: `web_search_enabled`, `search_context_size`
(`low`/`medium`/`high`), `allowed_domains`
- **Google**: `web_search_enabled`
## Backend
- `codersdk/chats.go` — new fields on the per-provider option structs
- `coderd/chatd/chatd.go` — `buildProviderTools()` reads config, creates
`ProviderDefinedTool` entries (uses `anthropic.WebSearchTool()` helper
from fantasy)
- `coderd/chatd/chatloop/chatloop.go` — `ProviderTools` on `RunOptions`,
merged into `Call.Tools`. Provider-executed tool calls skip local
execution. `StreamPartTypeToolResult` with `ProviderExecuted: true` is
accumulated inline (matching fantasy's own agent.go pattern) instead of
post-stream synthesis.
- `coderd/chatd/chatprompt/` — `MarshalToolResult` carries
`ProviderMetadata` through DB persistence so multi-turn round-trips work
(Anthropic needs `encrypted_content` back)
## Frontend
- Source citations render **inline** at the tool-call position (not
bottom-of-message), using `ToolCollapsible` so they look like other tool
cards — collapsed "Searched N results" with globe icon, expand to see
source pills
- Provider-executed tool calls/results are hidden from the normal tool
card UI
- Tool-role messages with only provider-executed results return `null`
(no empty bubble)
- Both persisted (messageParsing.ts) and streaming (streamState.ts)
paths group consecutive `source` parts into a single `{ type: "sources"
}` render block
## Fantasy changes
The fantasy fork (`kylecarbs/fantasy` branch `cj/go1.25`) has the
Anthropic tool code merged in, but will hopefully go upstream from:
https://github.com/charmbracelet/fantasy/pull/163
## Summary
Scale-tested the `chatd` package with mock-based benchmarks to identify
performance bottlenecks. This PR fixes 6 of the 8 identified issues,
ranked by severity.
## Changes
### 1. Parallel tool execution (HIGH) — `chatloop.go`
`executeTools` ran tool calls sequentially. Now dispatches all calls
concurrently via goroutines with `sync.WaitGroup`. Results are
pre-allocated by index (no mutex needed). `onResult` callbacks fire as
each tool completes.
### 2. Pubsub-backed subagent await (HIGH) — `subagent.go`
`awaitSubagentCompletion` polled the DB every 200ms. Now subscribes to
the child chat's `ChatStreamNotifyChannel` via pubsub for near-instant
notifications. Fallback poll reduced to 5s. Falls back to 200ms only
when `pubsub == nil` (single-instance / in-memory).
### 3. Per-chat stream locking (MEDIUM) — `chatd.go`
Replaced single global `streamMu` + `map[uuid.UUID]*chatStreamState`
with `sync.Map` where each `chatStreamState` has its own `sync.Mutex`.
Zero cross-chat contention.
### 4. Batch chat acquisition (MEDIUM) — `chatd.go`
`processOnce` acquired 1 chat per tick. Now loops up to
`maxChatsPerAcquire = 10` per tick, avoiding idle time when many chats
are pending.
### 5. Reduced heartbeat frequency (LOW-MEDIUM) — `chatd.go`
`chatHeartbeatInterval` changed from 30s to 60s. Safe given the 5-minute
`DefaultInFlightChatStaleAfter`.
### 6. O(depth) descendant check (LOW) — `subagent.go`
Replaced top-down BFS (`O(total_descendants)` queries) with bottom-up
parent-chain walk (`O(depth)` queries). Includes cycle protection.
## Not addressed (intentionally)
- Message serialization overhead
- Buffer eviction (`buffer[1:]` pattern)
Removes the backend and frontend logic that extracted compact titles
from reasoning/thinking blocks. The `Title` field on `ChatMessagePart`
remains for other part types (e.g. source), but reasoning blocks no
longer have titles derived from first-line markdown bold text or
provider metadata summaries.
**Backend:**
- Remove `ReasoningTitleFromFirstLine`, `reasoningTitleFromContent`,
`reasoningSummaryTitle`, `compactReasoningSummaryTitle`, and
`reasoningSummaryHeadline` from chatprompt
- Simplify `marshalContentBlock` to plain `json.Marshal` (no title
injection)
- Remove title tracking maps and `setReasoningTitleFromText` from
chatloop stream processing
- Remove `reasoningStoredTitle` from db2sdk
- Remove related tests from db2sdk_test
**Frontend:**
- Remove `mergeThinkingTitles` from blockUtils
- Simplify `appendTextBlock` to always merge consecutive thinking blocks
- Remove `applyStreamThinkingTitle` from streamState
- Simplify reasoning/thinking stream handler to ignore title-only parts
- Update tests accordingly
Net: **-487 lines / +42 lines**
Split from #22693 per review feedback.
Fixes multiple bugs in coderd/chatd and sub-packages including race
conditions, transaction safety, stream buffer bounds, retry limits, and
enterprise relay improvements.
See commit message for full list.
## Problem
Three bugs with chat summarization (compaction) share a single root
cause: `ReloadMessages` was never wired up in the production
`chatloop.Run()` call.
### Bug 1: Compaction never fires between steps
The inline compaction guard in `chatloop.go` requires both `Compaction`
and `ReloadMessages` to be non-nil:
```go
if opts.Compaction != nil && opts.ReloadMessages != nil {
```
Since `ReloadMessages` was only set in tests, inline compaction was
**dead code in production**. Long multi-step turns could blow through
the context window.
### Bug 2: Compaction only occurs at end of turn
The post-run safety net doesn't check `ReloadMessages`, so it was the
only compaction path that fired:
```go
if !alreadyCompacted && opts.Compaction != nil { // no ReloadMessages check
```
This meant compaction only happened once, after the entire agent turn
finished.
### Bug 3: Agent stops after summarization
After post-run compaction, `Run()` unconditionally returned `nil`.
`processChat` then set the chat status to `waiting` (done). The agent
never had a chance to continue with its fresh summarized context.
## Fix
1. **Wire up `ReloadMessages`** in `chatd.go`: reloads persisted
messages from the database and re-applies system prompts (subagent
instruction, workspace AGENTS.md).
2. **Wrap the step loop in an outer compaction loop**: when compaction
fires on the model's final step (`compactedOnFinalStep`), reload
messages and `continue` the outer loop so the agent re-enters with
summarized context.
3. **Track `compactedOnFinalStep`** to distinguish inline compaction on
the last step (needs re-entry) from inline compaction mid-loop followed
by more tool-call steps (agent already consumed the compacted context,
no re-entry needed).
4. **Add `maxCompactionRetries = 3`** to prevent infinite compaction
loops.
## Testing
- All 7 existing compaction tests pass unchanged.
- Added `PostRunCompactionReEntersStepLoop` test: verifies that when a
text-only response triggers compaction, the outer loop re-enters and the
agent makes a second stream call with fresh context.
Kyle Carberry