Add Ollama MCP server so the container agent can call local models and optionally manage the Ollama model library.
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tessl review fix ./.claude/skills/add-ollama-tool/SKILL.mdThis skill adds a stdio-based MCP server that exposes local Ollama models as tools for the container agent. Claude remains the orchestrator but can offload work to local models served by the Ollama daemon on the host, and can optionally manage the model library directly. Ollama runs locally and is keyless — there are no credentials to thread; the only configuration is the daemon's base URL.
Core tools (always available):
ollama_list_models — list installed models with name, size, and family (GET /api/tags)ollama_generate — send a prompt to a specified model and return the response (POST /api/generate)Management tools (opt-in via OLLAMA_ADMIN_TOOLS=true):
ollama_pull_model — pull (download) a model from the Ollama registry (POST /api/pull)ollama_delete_model — delete a locally installed model to free disk space (DELETE /api/delete)ollama_show_model — show model details: modelfile, parameters, and architecture info (POST /api/show)ollama_list_running — list models currently loaded in memory with memory usage and processor type (GET /api/ps)The skill ships the MCP server source (and its tests) in this folder and copies them into the agent-runner tree at install time, then registers the server in index.ts and forwards host env vars in container-runner.ts. Registering the server is enough to expose its tools — the agent's allow-pattern (mcp__ollama__*) is derived from the registered server name.
Check if container/agent-runner/src/ollama-mcp-stdio.ts exists. If it does, skip to Phase 3 (Configure).
Verify Ollama is installed and its daemon is reachable. On the host:
curl -s http://127.0.0.1:11434/api/tags | headIf the request fails:
ollama serve).curl -s http://127.0.0.1:11434/api/tags.If no models are installed, suggest pulling one:
You need at least one model. For example:
ollama pull gemma3:1b # Small, fast (~1GB) ollama pull llama3.2 # Good general purpose (~2GB) ollama pull qwen3-coder:30b # Best for code tasks (~18GB)
This skill reaches into both the container (Bun) tree and the host (Node) tree, so its files go into both, alongside the integration points they cover.
S=.claude/skills/add-ollama-tool
# Container (Bun) tree — the MCP server and the registration wiring test
cp $S/ollama-mcp-stdio.ts container/agent-runner/src/ollama-mcp-stdio.ts
cp $S/ollama-registration.test.ts container/agent-runner/src/ollama-registration.test.ts
# Host (Node) tree — the env-forwarding helper and the wiring test
cp $S/ollama-env.ts src/ollama-env.ts
cp $S/ollama-wiring.test.ts src/ollama-wiring.test.tsEdit container/agent-runner/src/index.ts. Find the mcpServers object that currently looks like this:
const mcpServers: Record<string, { command: string; args: string[]; env: Record<string, string> }> = {
nanoclaw: {
command: 'bun',
args: ['run', mcpServerPath],
env: {},
},
};Add an ollama entry alongside nanoclaw:
const mcpServers: Record<string, { command: string; args: string[]; env: Record<string, string> }> = {
nanoclaw: {
command: 'bun',
args: ['run', mcpServerPath],
env: {},
},
ollama: {
command: 'bun',
args: ['run', path.join(__dirname, 'ollama-mcp-stdio.ts')],
env: {
...(process.env.OLLAMA_HOST ? { OLLAMA_HOST: process.env.OLLAMA_HOST } : {}),
...(process.env.OLLAMA_ADMIN_TOOLS ? { OLLAMA_ADMIN_TOOLS: process.env.OLLAMA_ADMIN_TOOLS } : {}),
},
},
};ollama-registration.test.ts asserts this entry is present and points at the server module — the tool only appears to the agent if it is registered here.
The container receives TZ and OneCLI networking vars by default; any other host env
var the MCP subprocess needs must be forwarded explicitly. The forwarding logic lives in
the copied src/ollama-env.ts (ollamaEnv()) — OLLAMA_HOST (the daemon base URL)
and OLLAMA_ADMIN_TOOLS (the library-management opt-in flag). Both are configuration, not
credentials (Ollama itself is local and keyless), so they belong on the composed env
literal — a credential-NAMED key would need the contributedEnv lane instead (see
add-atomic-chat-tool for that shape).
Import it in src/container-runner.ts (alongside the other local imports):
import { ollamaEnv } from './ollama-env.js';Then, in composeSessionSpec, find the env literal (the TZ line) and spread the helper right after it:
const env: Record<string, string> = {
TZ: containerConfig.timezone ?? TIMEZONE,
...ollamaEnv(),
};ollama-wiring.test.ts asserts this ...ollamaEnv() spread exists inside composeSessionSpec.
[OLLAMA] log lines at info levelShared block. This rewrites the driver's container-stderr logger, which other local-model tools (e.g.
add-atomic-chat-toolfor[ATOMIC]) also edit to surface their own prefix. Touch only the[OLLAMA]branch and leave the rest of the block intact, so the edits coexist and removal restores it cleanly.
Container stderr now lands in the Docker driver: in src/drivers/docker-driver.ts, inside DockerHandle.start(), find the stderr handler:
proc.onStderr((line) => {
log.debug(line, { container: this.name });
this.#stderrTail.push(line);
if (this.#stderrTail.length > 10) this.#stderrTail.shift();
});Replace the log.debug line with a prefix branch (leave the stderr-tail lines intact — they feed the non-zero-exit warning):
proc.onStderr((line) => {
if (line.includes('[OLLAMA]')) {
log.info(line, { container: this.name });
} else {
log.debug(line, { container: this.name });
}
this.#stderrTail.push(line);
if (this.#stderrTail.length > 10) this.#stderrTail.shift();
});If add-atomic-chat-tool (or another local-model tool) has already turned this into a
multi-branch block, just add an else if (line.includes('[OLLAMA]')) branch instead of
replacing it.
.env.exampleAppend to .env.example:
# Ollama MCP tool (.claude/skills/add-ollama-tool)
# Override the host where the Ollama daemon listens.
# Default: http://host.docker.internal:11434 (with fallback to localhost)
# OLLAMA_HOST=http://host.docker.internal:11434
# Opt in to library-management tools (pull, delete, show, list-running).
# Leave unset to expose only list + generate.
# OLLAMA_ADMIN_TOOLS=truepnpm run build
pnpm exec tsc -p container/agent-runner/tsconfig.json --noEmit
# Host tree: composeSessionSpec wiring
pnpm exec vitest run src/ollama-wiring.test.ts
# Container tree: index.ts registration
(cd container/agent-runner && bun test src/ollama-registration.test.ts)
./container/build.shAll must be clean before proceeding. The wiring and registration tests confirm the two
integration points — the composeSessionSpec spread and the index.ts registration — are
actually in place; a failure means one drifted. (The MCP server's own request/response
behavior against the Ollama daemon is the author's build-time concern, not part of these
tests — verify it manually in Phase 4.)
Ask the user:
Would you like the agent to be able to manage Ollama models (pull, delete, inspect, list running)?
- Yes — adds tools to pull new models, delete old ones, show model info, and check what's loaded in memory
- No — the agent can only list installed models and generate responses (you manage models yourself on the host)
If the user wants management tools, add to .env:
OLLAMA_ADMIN_TOOLS=trueIf they decline (or don't answer), leave the variable unset — only list + generate are exposed.
By default, the MCP server connects to http://host.docker.internal:11434 (Docker Desktop) with a fallback to localhost. To use a custom Ollama host, add to .env:
OLLAMA_HOST=http://your-ollama-host:11434Run from your NanoClaw project root:
source setup/lib/install-slug.sh
launchctl kickstart -k gui/$(id -u)/$(launchd_label) # macOS
# Linux: systemctl --user restart $(systemd_unit)Tell the user:
Send a message like: "use ollama to tell me the capital of France"
The agent should use
ollama_list_modelsto find available models, thenollama_generateto get a response.
If OLLAMA_ADMIN_TOOLS=true was set, tell the user:
Send a message like: "pull the gemma3:1b model" or "which ollama models are currently loaded in memory?"
The agent should call
ollama_pull_modelorollama_list_runningrespectively.
tail -f logs/nanoclaw.log | grep -i ollamaLook for:
[OLLAMA] Listing models... — list request started[OLLAMA] Found N models — models discovered[OLLAMA] >>> Generating with <model> — generation started[OLLAMA] <<< Done: <model> | Xs | N tokens | M chars — generation completed[OLLAMA] Pulling model: — pull in progress (management tools)[OLLAMA] Deleted: — model removed (management tools)The agent is looking for an ollama CLI inside the container instead of using the MCP tools. This means:
container/agent-runner/src/ollama-mcp-stdio.ts existscontainer/agent-runner/src/index.ts has the ollama entry in mcpServers (the allow-pattern is derived from this, so registration is the only thing to check)./container/build.shcurl http://127.0.0.1:11434/api/tagsollama list on the host)docker run --rm curlimages/curl curl -s http://host.docker.internal:11434/api/tagsOLLAMA_HOST in .envmodel not found / 404 on generateThe model name passed to ollama_generate must exactly match one of the names returned by ollama_list_models (including any :tag suffix, e.g. gemma3:1b). Ask the agent to list models first, then pick one from that list.
ollama_pull_model times out on large modelsLarge models (7B+) can take several minutes. The tool uses stream: false so it blocks until the pull completes — this is intentional. For very large pulls, use the host CLI directly: ollama pull <model>.
Ensure OLLAMA_ADMIN_TOOLS=true is set in .env and the service was restarted after adding it. The management tools are only registered when that flag is present in the container's environment.
Ollama lazy-loads models into memory on first use. The initial call may take longer while the model warms up. Subsequent calls against the same model are fast.
The agent may not know about the tools. Try being explicit: "use the ollama_generate tool with gemma3:1b to answer: ..."
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