Adds a deployment-wide admin override for general delegated subagents.
## What changed
- store the general override in `site_configs` and expose it through the
shared `agent-model-override/{context}` API
- apply the general override when spawning delegated general subagents,
while preserving the existing Explore override behavior
- reuse a shared Agents settings form for the general and Explore
override sections
## Validation
- `make gen`
- `go test ./coderd -run 'TestChatModelOverrides'`
- `go test ./coderd/x/chatd -run
'TestSpawnAgent_(GeneralUsesConfiguredModelOverride|GeneralOverrideLogsAndFallsBackWhenCredentialsUnavailable|GeneralOverrideLogsAndFallsBackWhenProviderDisabled)'`
- `pnpm -C site lint:types`
- `pnpm -C site test:storybook --
AgentSettingsAgentsPageView.stories.tsx`
- `make lint`
- `make pre-commit`
> Mux is acting on Mike's behalf.
Explore sub-agents previously could not use `web_search` or external MCP
tools. `runChat` hard-skipped both for Explore. Lifting those guards
naively would over-grant tools, because a child chat could outlive the
spawning turn's plan-mode filter.
This change persists the spawning parent turn's filtered external MCP
server IDs onto the child Explore chat, and simplifies the Explore
provider-tool filter in `runChat`:
- New `resolveExploreToolSnapshot` helper: computes the child's
inherited external MCP subset by running the parent's configs through
`filterExternalMCPConfigsForTurn` (plan-mode policy) and, if the parent
is itself an Explore child, further narrowing to the parent's own
persisted `MCPServerIDs`. The result is written to the child's
`MCPServerIDs` column at spawn time.
- The existing `mcp_server_ids` column is the sole durable snapshot. No
new chat column is added.
- `runChat` for Explore children: loads MCP tools from the persisted
snapshot, and keeps only `web_search` from provider-native tools (to
block computer-use and other write-style tools, since Explore is
read-only). Whether `web_search` is actually available is a per-model
decision, determined by the current model config, just like a main chat.
- Built-in Explore allowlist is unchanged. Workspace-local MCP remains
excluded for Explore.
Verification: `go build ./...`, `go test ./coderd/x/chatd/... -count=1`,
`make gen` (clean tree), `make lint/emdash`, `go vet`. Deep-review ran
12 reviewers on the feature and 5 on the clarity refactor; CAR reviewed
and approved; a subsequent scope reduction dropped a temporary
`allow_web_search` column in favor of per-model handling.
> Mux is acting on Mike's behalf.
Unify the three subagent spawn tools (`spawn_agent`,
`spawn_explore_agent`, `spawn_computer_use_agent`) behind a single
`spawn_subagent` tool keyed by a `subagent_type` discriminant
(`general`, `explore`, `computer_use`). Mirrors the single-entry-point
pattern already used by `task` in mux while keeping `wait_agent`,
`message_agent`, and `close_agent` as separate lifecycle tools.
A new backend subagent definition catalog
(`coderd/x/chatd/subagent_catalog.go`) is the source of truth for tool
description, prompt guidance, availability rules (plan mode,
desktop/Anthropic gating), and child-chat option building.
`spawn_subagent` advertises only the types available in the current
context and validates `subagent_type` server-side; context inheritance
still flows through the existing `createChildSubagentChatWithOptions`
path. `wait_agent`, `message_agent`, and `close_agent` responses now
include a server-derived `subagent_type` so the UI stops inferring
lifecycle state from tool names.
The frontend gets a shared normalization helper
(`site/src/pages/AgentsPage/components/ChatElements/tools/subagentDescriptor.ts`)
that maps either legacy tool names or new `spawn_subagent` args into a
common descriptor (action, variant, icon, fallback copy). Legacy
transcripts still render identically; `Tool.tsx`, `SubagentTool.tsx`,
`ToolLabel.tsx`, `ToolIcon.tsx`, and `messageParsing.ts` now key off the
descriptor instead of hard-coded names. Existing UI copy is preserved
(`Spawning Explore agent...`, `Using the computer...`, computer-use
monitor icon and Open Desktop affordance).
> This PR was opened by Mux working on Mike's behalf.
Michael Suchacz