add-gmail-tool

star 29.9k

Add Gmail as an MCP tool (read, search, send, label, draft) using OneCLI-managed OAuth. The agent gets Gmail tools in every enabled group; OneCLI injects real tokens at request time so no raw credentials are ever in the container or on disk in usable form.

nanocoai By nanocoai schedule Updated 6/6/2026
play_arrow Run Skill in Manus View GitHub

name: add-gmail-tool description: Add Gmail as an MCP tool (read, search, send, label, draft) using OneCLI-managed OAuth. The agent gets Gmail tools in every enabled group; OneCLI injects real tokens at request time so no raw credentials are ever in the container or on disk in usable form.

Add Gmail Tool (OneCLI-native)

This skill wires the @gongrzhe/server-gmail-autoauth-mcp stdio MCP server into selected agent groups. The MCP server reads stub credentials containing the onecli-managed placeholder; the OneCLI gateway intercepts outbound calls to gmail.googleapis.com and injects the real OAuth bearer from its vault.

Tools exposed (from gmail-mcp@1.1.11, surfaced to the agent as mcp__gmail__<name>): search_emails, read_email, send_email, draft_email, delete_email, modify_email, batch_modify_emails, batch_delete_emails, download_attachment, list_email_labels, create_label, update_label, delete_label, get_or_create_label, list_filters, get_filter, create_filter, create_filter_from_template, delete_filter.

Why this pattern: v2's invariant is that containers never receive raw API keys — OneCLI is the sole credential path (see CHANGELOG v2.0.0). The stub-file pattern satisfies this: the container sees "onecli-managed" placeholders, the gateway swaps them in flight.

Phase 1: Pre-flight

Verify OneCLI has Gmail connected

onecli apps get --provider gmail

Expected: "connection": { "status": "connected" } with scopes including gmail.readonly, gmail.modify, gmail.send.

If not connected, tell the user:

Open the OneCLI web UI at http://127.0.0.1:10254, go to Apps → Gmail, and click Connect. Sign in with the Google account you want the agent to act as.

Verify stub credentials exist

ls -la ~/.gmail-mcp/gcp-oauth.keys.json ~/.gmail-mcp/credentials.json 2>&1

If both exist and contain "onecli-managed":

grep -l onecli-managed ~/.gmail-mcp/gcp-oauth.keys.json ~/.gmail-mcp/credentials.json

...skip to Phase 2.

If either file exists but does not contain onecli-managed, STOP and tell the user — these are real OAuth credentials from a previous non-OneCLI install. Back them up, then delete before proceeding. The OneCLI migration normally handles this; if it didn't, something is wrong.

If both files are absent, write them now:

mkdir -p ~/.gmail-mcp
cat > ~/.gmail-mcp/gcp-oauth.keys.json <<'EOF'
{
  "installed": {
    "client_id": "onecli-managed.apps.googleusercontent.com",
    "client_secret": "onecli-managed",
    "redirect_uris": ["http://localhost:3000/oauth2callback"]
  }
}
EOF
cat > ~/.gmail-mcp/credentials.json <<'EOF'
{
  "access_token": "onecli-managed",
  "refresh_token": "onecli-managed",
  "token_type": "Bearer",
  "expiry_date": 99999999999999,
  "scope": "https://www.googleapis.com/auth/gmail.readonly https://www.googleapis.com/auth/gmail.modify https://www.googleapis.com/auth/gmail.send"
}
EOF
chmod 600 ~/.gmail-mcp/gcp-oauth.keys.json ~/.gmail-mcp/credentials.json

Verify mount allowlist covers the path

cat ~/.config/nanoclaw/mount-allowlist.json

~/.gmail-mcp must sit under an allowedRoots entry (e.g. /home/<user>). If it doesn't, tell the user to run /manage-mounts first or add their home directory.

Check agent secret-mode

For each target agent group, confirm OneCLI will inject Gmail secrets into its container. Find the OneCLI agent ID that matches the group's agentGroupId:

onecli agents list

If that agent's secretMode is all, you're done — Gmail secrets (identified by OneCLI's Gmail hostPattern) will auto-inject. If it's selective, explicitly assign the Gmail secrets using the safe merge pattern (set-secrets replaces the entire list — always read first):

GMAIL_IDS=$(onecli secrets list | jq -r '[.data[] | select(.name | test("(?i)gmail")) | .id] | join(",")')
CURRENT=$(onecli agents secrets --id <agent-id> | jq -r '[.data[]] | join(",")')
MERGED=$(printf '%s' "$CURRENT,$GMAIL_IDS" | tr ',' '\n' | sort -u | paste -sd ',' -)
onecli agents set-secrets --id <agent-id> --secret-ids "$MERGED"
onecli agents secrets --id <agent-id>

Phase 2: Apply Code Changes

Check if already applied

grep -q 'GMAIL_MCP_VERSION' container/Dockerfile && \
echo "ALREADY APPLIED — skip to Phase 3"

Copy the skill's tests into the container tree

Both integration points this skill relies on live in the container (Bun) tree — the Dockerfile package install and the dynamic allow-pattern derivation in claude.ts — so the guards go there. cp overwrites, so re-running is safe.

S=.claude/skills/add-gmail-tool
cp $S/gmail-dockerfile.test.ts    container/agent-runner/src/providers/gmail-dockerfile.test.ts
cp $S/gmail-allow-pattern.test.ts container/agent-runner/src/providers/gmail-allow-pattern.test.ts
  • gmail-dockerfile.test.ts asserts the GMAIL_MCP_VERSION ARG and the pinned pnpm install -g line are present — the gmail-mcp binary is a Dockerfile-installed CLI, not importable or typed, so this structural guard is what goes red if the install is dropped.
  • gmail-allow-pattern.test.ts asserts claude.ts still spreads Object.keys(this.mcpServers).map(mcpAllowPattern) into allowedTools — the derivation that makes registering gmail (Phase 3) enough to expose mcp__gmail__*.

Add MCP server to Dockerfile

Edit container/Dockerfile. Find the pinned-version ARG block:

ARG CLAUDE_CODE_VERSION=2.1.154
ARG AGENT_BROWSER_VERSION=latest
ARG VERCEL_VERSION=52.2.1
ARG BUN_VERSION=1.3.12

Add a new line:

ARG GMAIL_MCP_VERSION=1.1.11

Then find the last pnpm global-install RUN block (the one that installs @anthropic-ai/claude-code) and add a new block directly after it (before the # ---- ncl CLI wrapper section):

RUN --mount=type=cache,target=/root/.cache/pnpm \
    pnpm install -g \
        "@gongrzhe/server-gmail-autoauth-mcp@${GMAIL_MCP_VERSION}" \
        "zod-to-json-schema@3.22.5"

Pinned version matters — minimumReleaseAge in pnpm-workspace.yaml gates trunk installs, and CLAUDE.md requires a fixed ARG version for all Node CLIs installed into the image.

Why the zod-to-json-schema pin: @gongrzhe/server-gmail-autoauth-mcp@1.1.11 has loose deps (zod-to-json-schema: ^3.22.1, zod: ^3.22.4). pnpm resolves zod-to-json-schema to the latest 3.25.x, which imports zod/v3 — a subpath that only exists in zod>=3.25. But zod resolves to 3.24.x (highest satisfying ^3.22.4 without breaking peer ranges). Result: ERR_PACKAGE_PATH_NOT_EXPORTED at import time. Pinning zod-to-json-schema to a pre-v3-subpath version avoids it. Re-check if you bump GMAIL_MCP_VERSION.

The Gmail allow-pattern is derived automatically. container/agent-runner/src/providers/claude.ts builds allowedTools from each group's mcpServers map (Object.keys(this.mcpServers).map(mcpAllowPattern)), so registering gmail in Phase 3 exposes mcp__gmail__* to the agent.

Rebuild the container image

./container/build.sh

Must complete cleanly. The new pnpm install -g layer is ~60s first time (cached on rebuild).

Phase 3: Wire Per-Agent-Group

For each agent group that should have Gmail (ask the user — typically their personal DM and CLI agents, sometimes shared household agents), persist two changes to the central DB (data/v2.db): the mcpServers.gmail entry and an additionalMounts entry for .gmail-mcp. Both flow through materializeContainerJson on every spawn, so editing groups/<folder>/container.json by hand does not stick — that file is regenerated from the DB.

List groups, pick which ones get Gmail

ncl groups list

Register the MCP server

For each chosen <group-id>:

ncl groups config add-mcp-server \
  --id <group-id> \
  --name gmail \
  --command gmail-mcp \
  --args '[]' \
  --env '{"GMAIL_OAUTH_PATH":"/workspace/extra/.gmail-mcp/gcp-oauth.keys.json","GMAIL_CREDENTIALS_PATH":"/workspace/extra/.gmail-mcp/credentials.json"}'

Approval behaviour depends on where you run it: from inside an agent's container ncl write verbs are approval-gated (admin approves before it lands); from a host operator shell with full scope, it executes immediately. Either way, the response tells you which path it took.

Add the .gmail-mcp mount

There is no ncl groups config add-mount verb yet (tracked in #2395). Until that ships, edit the DB directly via the in-tree wrapper (scripts/q.ts — setup/verify.ts:5 codifies that NanoClaw avoids depending on the sqlite3 CLI binary, so don't shell out to it):

GROUP_ID='<group-id>'
HOST_PATH="$HOME/.gmail-mcp"
MOUNT=$(jq -cn --arg h "$HOST_PATH" '{hostPath:$h, containerPath:".gmail-mcp", readonly:false}')
pnpm exec tsx scripts/q.ts data/v2.db "UPDATE container_configs \
  SET additional_mounts = json_insert(additional_mounts, '\$[#]', json('$MOUNT')), \
      updated_at = datetime('now') \
  WHERE agent_group_id = '$GROUP_ID';"

Run from your NanoClaw project root (where data/v2.db lives). The $[#] placeholder is SQLite JSON1's append-to-end notation; it's \$-escaped so bash doesn't arithmetic-expand it before sqlite sees it. updated_at is ISO-string everywhere else in the schema, so use datetime('now') — not strftime('%s','now'), which would silently mix epoch ints into a column of YYYY-MM-DD HH:MM:SS strings.

Switch to ncl groups config add-mount once #2395 lands. Update this skill at that time.

Why the container path is relative: mount-security rejects absolute containerPath values. Additional mounts are prefixed with /workspace/extra/, so containerPath: ".gmail-mcp" lands at /workspace/extra/.gmail-mcp. The MCP server's GMAIL_OAUTH_PATH / GMAIL_CREDENTIALS_PATH env vars point at that absolute location inside the container.

Why this can't be groups/<folder>/container.json: post-migration 014-container-configs, materializeContainerJson in src/container-config.ts rewrites that file from the DB on every spawn. Anything hand-edited there is silently overwritten on next restart.

Phase 4: Build, Validate, Restart

pnpm run build
pnpm exec tsc -p container/agent-runner/tsconfig.json --noEmit
(cd container/agent-runner && bun test src/providers/gmail-dockerfile.test.ts src/providers/gmail-allow-pattern.test.ts)

All must be clean before proceeding. gmail-dockerfile.test.ts confirms the package install is wired into the image; gmail-allow-pattern.test.ts confirms the allow-pattern derivation that exposes mcp__gmail__*. A failure means one drifted.

Run from your NanoClaw project root:

source setup/lib/install-slug.sh
launchctl kickstart -k gui/$(id -u)/$(launchd_label)  # macOS
systemctl --user restart $(systemd_unit)              # Linux

Phase 5: Verify

Test from the wired agent

Tell the user:

In your <agent-name> chat, send: "list my gmail labels" or "search my inbox for invoices from last month".

The agent should use mcp__gmail__list_labels / mcp__gmail__search. The first call may take a second or two while the MCP server starts and OneCLI does the token exchange.

Check logs if the tool isn't working

tail -100 logs/nanoclaw.log logs/nanoclaw.error.log | grep -iE 'gmail|mcp'
# Per-container logs — session-scoped:
ls data/v2-sessions/*/stderr.log | head

Common signals:

  • command not found: gmail-mcp → image wasn't rebuilt or PATH doesn't include /pnpm (should — ENV PATH="$PNPM_HOME:$PATH" in Dockerfile).
  • ENOENT: no such file or directory, open '/workspace/extra/.gmail-mcp/credentials.json' → mount is missing. Check ~/.config/nanoclaw/mount-allowlist.json includes a parent of ~/.gmail-mcp.
  • 401 Unauthorized from gmail.googleapis.com → OneCLI isn't injecting. Check the agent's secret mode (onecli agents secrets --id <agent-id>) and that the Gmail app is connected (onecli apps get --provider gmail).
  • Agent says "I don't have Gmail tools" → the gmail MCP server isn't registered in this group's mcpServers (re-run the ncl groups config add-mcp-server step in Phase 3 for that group and restart it), or the agent-runner image is stale (rebuild with ./container/build.sh, with --no-cache if suspicious).

Removal

See REMOVE.md for the idempotent removal procedure (delete the copied tests, unregister the MCP server per group, drop the mount, remove the Dockerfile install, rebuild, and optionally drop the stubs and disconnect OneCLI).

Notes

  • Stub format is OneCLI-prescribed. The access_token: "onecli-managed" pattern with expiry_date: 99999999999999 tells the Google auth client the token is valid; OneCLI intercepts the outgoing Gmail API call and rewrites Authorization: Bearer onecli-managed to the real token. expiry_date: 0 (refresh-interception) is an alternative the OneCLI docs describe — both work but OneCLI's own migrate command writes the far-future variant, which is what this skill assumes.
  • Scopes are set at OAuth connect time. If the agent needs scopes beyond what's currently connected (e.g. the user later wants calendar.readonly for combined email/calendar workflows), disconnect and reconnect Gmail in the OneCLI web UI with the expanded scope set.
  • This is tool-only. Inbound email as a channel (emails trigger the agent) is a separate piece of work — it needs a src/channels/gmail.ts adapter that polls the inbox and routes to a messaging group. The pre-v2 qwibitai skill had this; it has not been ported to v2's channel architecture as of v2.0.0.

Credits & references

  • MCP server: @gongrzhe/server-gmail-autoauth-mcp by GongRzhe — MIT-licensed.
  • OneCLI credential stubs: pattern documented at https://onecli.sh/docs/guides/credential-stubs/gmail.md.
  • Skill pattern: modeled on add-atomic-chat-tool and add-vercel.
  • Addresses: issue #1500 (proxy Gmail/Calendar OAuth tokens through credential proxy) for the Gmail side.
  • Related PRs: #1810 (pre-install Gmail/Notion MCP) overlaps on the "install the MCP server in the image" idea but bundles many unrelated changes; this skill is the focused OneCLI-native version.
Install via CLI
npx skills add https://github.com/nanocoai/nanoclaw --skill add-gmail-tool
Repository Details
star Stars 29,890
call_split Forks 12,876
navigation Branch main
article Path SKILL.md
Occupations
Software Developers
More from Creator
nanocoai
nanocoai Explore all skills →