Removes the six task-management tools from the MCP tool surface in
`codersdk/toolsdk`:
- `coder_create_task`
- `coder_delete_task`
- `coder_list_tasks`
- `coder_get_task_status`
- `coder_send_task_input`
- `coder_get_task_logs`
Both the coderd-hosted MCP server (`coderd/mcp`) and the CLI `coder exp
mcp server` derive their tool list from `toolsdk.All`, so removing the
registry entries removes the tools from both servers with no server-side
changes.
The MCP server documentation (`docs/ai-coder/mcp-server.md`) is updated
to drop the task-management entry from the tool overview.
## What stays
- `coder_report_task` is intentionally kept: it is the agent-side
status-reporting mechanism (`WithTaskReporter`), already excluded from
the hosted MCP server, and required by `coder exp mcp server`, Claude
Code configuration, and scaletest.
- The `codersdk` Task SDK methods (`CreateTask`, `DeleteTask`, `Tasks`,
`TaskLogs`, etc.) and the Tasks feature (CLI, UI, API) are untouched;
this PR only removes MCP tool registration.
- The task-only `taskIDDescription` helper is deleted; `userDescription`
stays (used by `coder_create_workspace`).
The code change is deletion-only: 970 removed lines across `toolsdk.go`
and its test file, no added behavior.
## Validation
- `go build ./...`, `go test ./coderd/mcp/`, and targeted
`golangci-lint` pass. `go test ./codersdk/toolsdk/` passes all tests;
the package-level goleak failure (agentssh goroutines) reproduces
identically on unmodified `main` and is unrelated to this diff.
- `pnpm run lint-docs` passes on the docs change.
- Remote dogfood UAT ran against the toolsdk change and passed:
`tools/list` on both the hosted MCP endpoint and `coder exp mcp server`
confirms the six tools are absent and the remaining surface is intact
(34 hosted tools; CLI adds `search`/`fetch`), a `tools/call` of
`coder_get_authenticated_user` succeeds, and calling a removed tool
returns `-32602 unknown tool`. `coder_report_task` still registers in
the CLI server when `CODER_MCP_APP_STATUS_SLUG` is set.
- The failing `Pixel / Review` commit status is unrelated: this PR
contains no `site/` changes, and the same status fails on the last 8
`main` commits including this PR's merge base (`676b9bb06bf`).
> Mux acted on Mike's behalf to create this pull request.
Exposes the experimental Coder Agents chats API through the MCP tool
registry, so MCP clients (the hosted `/api/experimental/mcp/http` server
and `coder exp mcp server`) can start and drive server-side coding
agents.
New tools in `codersdk/toolsdk`, all thin wrappers over existing
`codersdk.ExperimentalClient` methods:
| Tool | Wraps |
|---|---|
| `coder_create_chat` | `CreateChat` (prompt, optional org, model
config, labels) |
| `coder_get_chat` | `GetChat` (status, last error, last turn summary,
workspace, files) |
| `coder_get_chat_messages` | `GetChatMessages` (user-facing parts,
chronological, cursor pagination, queued prompts) |
| `coder_send_chat_message` | `CreateChatMessage` (queue or interrupt
busy behavior) |
| `coder_interrupt_chat` | `InterruptChat` |
| `coder_archive_chat` | `UpdateChat` with `archived: true` |
| `coder_list_chat_model_configs` | `ListChatModelConfigs` (enabled
configs with default flag) |
Both MCP servers register tools from `toolsdk.All`, so no additional
wiring is needed. Responses are trimmed to what an MCP caller needs (IDs
as strings, user-facing transcripts) rather than full SDK payloads. No
new endpoints and no database changes.
Also adds MCP
[prompts](https://modelcontextprotocol.io/specification/2026-07-28/server/prompts)
for the chat workflows, defined once in `codersdk/toolsdk` and
registered by both servers:
| Prompt | Purpose |
|---|---|
| `coder_agents_delegate` | delegate a task to a Coder Agents chat and
monitor it to completion |
| `coder_agents_check` | check the status and recent activity of an
existing chat |
Each prompt declares the tools its workflow needs; the stdio server
skips prompts whose tools are excluded by `--allowed-tools`.
Tests run the tools against a chat-enabled coderdtest instance (fake
OpenAI-compatible provider plus in-process AI bridge), covering the full
lifecycle, an interrupt against a blocked turn, pagination cursors,
permission-dependent model config filtering, and argument validation.
Prompt coverage spans SDK rendering, the hosted
`prompts/list`/`prompts/get` round trip, and the stdio server including
allowlist gating.
> Mux created this PR on Mike's behalf.
## Stack Context
PR 6 of 6 in a stack that migrates every Coder MCP surface from the
archived `github.com/mark3labs/mcp-go` library to the official
`github.com/modelcontextprotocol/go-sdk` v1.7.0.
Stack: #28056 -> #28057 -> #28058 -> #28059 -> #28060 -> #28061
## Why
With every production surface migrated, this PR removes the mark3labs
dependency entirely and converts the remaining test fixtures.
- Migrates the remaining mark3labs test fixtures (coderd MCP e2e tests,
chatd fixtures, mcpclient fixtures, and the Force On MCP policy tests)
to official stateless SDK servers.
- Removes `github.com/mark3labs/mcp-go` from `go.mod` and drops the
corresponding dependabot ignore entry. Zero references remain repo-wide.
- Updates the MCP docs for the 2026-07-28 protocol: stateless Streamable
HTTP behavior, the supported 2024-11-05 through 2026-07-28 protocol
range, and explicit non-features (resources, prompts, structured output,
elicitation, MCP Tasks).
- The e2e ping assertion is removed because MCP 2026-07-28 removed the
ping method.
> Mux created this PR on Mike's behalf.
The MCP Registry rejects our `server.json` remote because the URL uses
`{coder_url}` as the entire base. Registry validation requires remote
URLs to literally begin with `https://`, and template variables are only
allowed after the scheme/host. The previous value
(`{coder_url}/api/experimental/mcp/http`) fails both the JSON schema
`^https?://[^\s]+$` pattern and the semantic remote-URL check.
## Changes
- Use `https://{coder_hostname}/api/experimental/mcp/http` with a
`coder_hostname` variable (users now enter a hostname like
`coder.example.com` instead of a full URL).
- Update the VS Code registry instructions in
`docs/ai-coder/mcp-server.md` to ask for the deployment hostname.
Verified with `mcp-publisher validate` against
`registry.modelcontextprotocol.io`:
```
Validating against https://registry.modelcontextprotocol.io...
✅ server.json is valid
```
This was caught by running the `Publish to MCP Registry` workflow in
validate-only mode (`publish: false`) before any real publish, so
nothing broken reached the public registry.
<details>
<summary>Root cause detail</summary>
The registry validator (`internal/validators`) substitutes known
template variables, then parses the URL. Because `{coder_url}` replaces
the whole scheme+host, the parsed URL has no scheme and is rejected as
an invalid remote URL. Hard-coding `https://` and scoping the variable
to the host satisfies both the schema pattern and `IsValidRemoteURL`
(which also requires `https`). The registry mandates `https` for remotes
regardless, so there is no loss of functionality.
</details>
---
_Generated with Coder Agents._
## Summary
This adds the necessary configuration to publish Coder's remote MCP
server to the official MCP Registry at registry.modelcontextprotocol.io.
## Changes
- **`server.json`**: MCP server metadata for registry discovery
- **`.github/workflows/publish-mcp-registry.yaml`**: GitHub Actions
workflow to automatically publish on release
## How it works
1. When a new Coder release is published, the workflow automatically
publishes to the MCP Registry
2. MCP clients (Claude, ChatGPT, VS Code, etc.) can discover Coder via
the registry
3. Users just need to provide their Coder deployment URL - OAuth handles
authentication automatically via RFC 7591 Dynamic Client Registration
## MCP Registry Entry
The server will be listed as `io.github.coder/coder` with:
- **Transport**: `streamable-http`
- **Endpoint**: `{coder_url}/api/experimental/mcp/http`
- **Auth**: OAuth2 (automatic via
`/.well-known/oauth-authorization-server`)
## Testing
After merge and next release, verify at:
```bash
curl "https://registry.modelcontextprotocol.io/v0.1/servers?q=io.github.coder"
```
Closes#21275
---
_Generated with `mux` • Model: `anthropic:claude-opus-4-5` • Thinking:
`medium`_
---------
Co-authored-by: Ben Potter <me@bpmct.net>
Updated toolsdk documentation link to the latest version.
If you have used AI to produce some or all of this PR, please ensure you
have read our [AI Contribution
guidelines](https://coder.com/docs/about/contributing/AI_CONTRIBUTING)
before submitting.
Michael Suchacz