Add read-only Buzz client entrypoint

Expose the existing stdio server to a dedicated Buzz agent without granting mutation tools or leaking unrelated runtime credentials. Document the verified Hermes and Buzz client paths. Co-authored-by: fredamn76 <fredrik.fallman@gmail.com> Signed-off-by: fredamn76 <fredrik.fallman@gmail.com>
2026-07-31 10:35:34 +02:00
parent c8775ac713
commit 242bb15641
6 changed files with 262 additions and 1 deletions
@@ -42,6 +42,57 @@ Create the Mealie token at `/user/profile/api-tokens`.
 Home Assistant is optional and isolated: without `HA_BASE_URL` and `HA_TOKEN`
 everything except `shopping_list_add` works normally.

+## Client integration
+
+### Hermes
+
+Hermes runs this server over stdio. The credential stays in
+`~/.hermes/.env`; `config.yaml` contains only environment placeholders.
+
+```bash
+hermes mcp add mealie \
+  --command /home/fredrik/.local/bin/uv \
+  --connect-timeout 60 \
+  --env 'MEALIE_API_TOKEN=${MEALIE_API_TOKEN}' \
+        'MEALIE_BASE_URL=${MEALIE_BASE_URL}' \
+        'MEALIE_USER_AGENT=Mealie-MCP/0.1' \
+  --args --directory /home/fredrik/.buzz/REPOS/mealie-mcp run mealie-mcp
+
+hermes config set mcp_discovery_timeout 10
+hermes mcp test mealie
+```
+
+The normal `hermes chat` client and the long-running gateway wait for MCP
+discovery. On the Hermes version used for the P1 acceptance test,
+`hermes -z` could snapshot its tools before a slower stdio server finished
+discovery; use the normal chat/gateway path for this server until that
+one-shot startup issue is fixed.
+
+### Buzz managed agent
+
+Buzz's managed-agent harness accepts one per-agent MCP executable. Set the
+dedicated Recept agent's MCP command to this read-only launcher:
+
+```text
+/home/fredrik/.buzz/REPOS/mealie-mcp/scripts/run-mealie-mcp-read-only-for-buzz
+```
+
+It contains search, read, scaling, organizer, duplicate-check, suggestion, and
+verification tools, but no import, patch, delete, ingredient-parse, image, or
+shopping-list tools. Switch to the full `mealie-mcp` entry point only after the
+separate write acceptance test has passed.
+
+The launcher reads only `MEALIE_API_TOKEN`, `MEALIE_BASE_URL`, and
+`MEALIE_USER_AGENT` from `~/.hermes/.env`, then starts the same stdio server
+with a clean environment. It does not place the token in the agent prompt,
+agent definition, command line, or Codex configuration.
+
+Keep this configuration agent-specific. Adding Mealie globally to
+`~/.codex/config.toml` would make the tools available to every Codex-based
+Buzz agent on the host, which is broader access than the private Recept agent
+needs. No HTTP transport is required while the agent and server run on the
+same machine.
+
 ## Tools

 **Read**
@@ -105,7 +156,7 @@ file tools; folding it in would make this server two things at once.
 ## Tests

 ```bash
-python -m pytest
+uv run --extra dev python -m pytest
 ```

 The suite covers the verified failure modes: Cloudflare 1010 vs 401, decimal-comma
@@ -38,6 +38,19 @@ RESOURCE_DIR = Path(__file__).parent / "resources"

 mcp = MCPServer("mealie", version="0.1.0")

+WRITE_TOOL_NAMES = frozenset(
+    {
+        "import_recipe_url",
+        "import_recipe_text",
+        "import_recipe_image",
+        "patch_recipe",
+        "delete_recipe",
+        "parse_ingredients",
+        "set_cover_image",
+        "shopping_list_add",
+    }
+)
+

 class MealieAuthError(RuntimeError):
    """The Mealie token is missing, expired, or wrong (HTTP 401)."""
@@ -745,3 +758,18 @@ instructions, and units (`msk`, `tsk`, `dl`, `krm`, `st`, `klyfta`).

 def main() -> None:
    mcp.run()
+
+
+def _configure_read_only(
+    server: MCPServer,
+    write_tool_names: frozenset[str] = WRITE_TOOL_NAMES,
+) -> None:
+    """Remove mutating tools before exposing the server to a read-only client."""
+    for name in sorted(write_tool_names):
+        server.remove_tool(name)
+
+
+def main_read_only() -> None:
+    """Run the same server without import, patch, delete, parse, image, or HA writes."""
+    _configure_read_only(mcp)
+    mcp.run()
@@ -10,6 +10,7 @@ dev = ["pytest>=8.0"]

 [project.scripts]
 mealie-mcp = "mealie_mcp.server:main"
+mealie-mcp-read-only = "mealie_mcp.server:main_read_only"

 [build-system]
 requires = ["hatchling"]
@@ -0,0 +1,79 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Buzz's managed-agent harness accepts one MCP executable per agent. Keep the
+# Mealie credential out of the agent definition by loading only the three
+# variables this server understands from the existing Hermes dotenv file.
+mealie_env_file="${MEALIE_ENV_FILE:-${HOME}/.hermes/.env}"
+mealie_repo_dir="${MEALIE_MCP_REPO_DIR:-/home/fredrik/.buzz/REPOS/mealie-mcp}"
+mealie_uv_bin="${MEALIE_UV_BIN:-/home/fredrik/.local/bin/uv}"
+
+mealie_token="${MEALIE_API_TOKEN:-}"
+mealie_base_url="${MEALIE_BASE_URL:-}"
+mealie_user_agent="${MEALIE_USER_AGENT:-}"
+
+clean_dotenv_value() {
+    local value="$1"
+    local first
+    local last
+
+    value="${value%$'\r'}"
+    if (( ${#value} >= 2 )); then
+        first="${value:0:1}"
+        last="${value: -1}"
+        if [[ "$first" == "$last" && ( "$first" == "'" || "$first" == '"' ) ]]; then
+            value="${value:1:${#value}-2}"
+        fi
+    fi
+    REPLY="$value"
+}
+
+if [[ -r "$mealie_env_file" ]]; then
+    while IFS= read -r line || [[ -n "$line" ]]; do
+        case "$line" in
+            MEALIE_API_TOKEN=*)
+                if [[ -z "$mealie_token" ]]; then
+                    clean_dotenv_value "${line#*=}"
+                    mealie_token="$REPLY"
+                fi
+                ;;
+            MEALIE_BASE_URL=*)
+                if [[ -z "$mealie_base_url" ]]; then
+                    clean_dotenv_value "${line#*=}"
+                    mealie_base_url="$REPLY"
+                fi
+                ;;
+            MEALIE_USER_AGENT=*)
+                if [[ -z "$mealie_user_agent" ]]; then
+                    clean_dotenv_value "${line#*=}"
+                    mealie_user_agent="$REPLY"
+                fi
+                ;;
+        esac
+    done < "$mealie_env_file"
+fi
+
+if [[ -z "$mealie_token" ]]; then
+    printf 'MEALIE_API_TOKEN is not set and was not found in %s\n' "$mealie_env_file" >&2
+    exit 1
+fi
+
+mealie_base_url="${mealie_base_url:-https://recept.famfallman.com}"
+mealie_user_agent="${mealie_user_agent:-Mealie-MCP/0.1}"
+
+# Do not forward the rest of the Desktop/Hermes environment to the MCP
+# subprocess. In particular, unrelated provider and platform tokens must not
+# become visible to this server. Export after sanitizing so the token is never
+# passed as a command-line argument to an intermediate `env` process.
+while IFS= read -r variable_name; do
+    case "$variable_name" in
+        HOME | PATH | LANG) ;;
+        *) unset "$variable_name" ;;
+    esac
+done < <(compgen -e)
+
+export MEALIE_API_TOKEN="$mealie_token"
+export MEALIE_BASE_URL="$mealie_base_url"
+export MEALIE_USER_AGENT="$mealie_user_agent"
+
+exec "$mealie_uv_bin" --directory "$mealie_repo_dir" run mealie-mcp-read-only
@@ -0,0 +1,79 @@
+from __future__ import annotations
+
+import os
+import subprocess
+from pathlib import Path
+
+
+LAUNCHER = (
+    Path(__file__).parents[1] / "scripts" / "run-mealie-mcp-read-only-for-buzz"
+)
+
+
+def _fake_uv(tmp_path: Path) -> Path:
+    executable = tmp_path / "fake-uv"
+    executable.write_text(
+        "#!/usr/bin/env bash\n"
+        "printf '%s\\n' \"${MEALIE_API_TOKEN}|${MEALIE_BASE_URL}|"
+        "${MEALIE_USER_AGENT}|${UNRELATED_SECRET-unset}|$*\"\n",
+        encoding="utf-8",
+    )
+    executable.chmod(0o755)
+    return executable
+
+
+def test_launcher_reads_only_mealie_values_and_clears_unrelated_secrets(
+    tmp_path: Path,
+) -> None:
+    env_file = tmp_path / "hermes.env"
+    env_file.write_text(
+        "OTHER_PROVIDER_TOKEN=must-not-leak\n"
+        "MEALIE_API_TOKEN='test-token'\n"
+        "MEALIE_BASE_URL=https://mealie.example\n"
+        'MEALIE_USER_AGENT="Test-Agent/1.0"\n',
+        encoding="utf-8",
+    )
+    env = {
+        **os.environ,
+        "MEALIE_ENV_FILE": str(env_file),
+        "MEALIE_MCP_REPO_DIR": "/tmp/test-repo",
+        "MEALIE_UV_BIN": str(_fake_uv(tmp_path)),
+        "UNRELATED_SECRET": "must-not-leak",
+    }
+
+    result = subprocess.run(
+        [str(LAUNCHER)],
+        check=False,
+        capture_output=True,
+        text=True,
+        env=env,
+    )
+
+    assert result.returncode == 0
+    assert result.stdout.strip() == (
+        "test-token|https://mealie.example|Test-Agent/1.0|unset|"
+        "--directory /tmp/test-repo run mealie-mcp-read-only"
+    )
+    assert "must-not-leak" not in result.stdout
+
+
+def test_launcher_fails_without_mealie_token(tmp_path: Path) -> None:
+    env_file = tmp_path / "empty.env"
+    env_file.write_text("MEALIE_BASE_URL=https://mealie.example\n", encoding="utf-8")
+    env = {
+        "HOME": str(tmp_path),
+        "PATH": os.environ["PATH"],
+        "MEALIE_ENV_FILE": str(env_file),
+        "MEALIE_UV_BIN": str(_fake_uv(tmp_path)),
+    }
+
+    result = subprocess.run(
+        [str(LAUNCHER)],
+        check=False,
+        capture_output=True,
+        text=True,
+        env=env,
+    )
+
+    assert result.returncode == 1
+    assert "MEALIE_API_TOKEN is not set" in result.stderr
@@ -1,8 +1,11 @@
 """Boundary contracts for the verified Mealie instance quirks."""
 from __future__ import annotations

+import asyncio
+
 import httpx
 import pytest
+from mcp.server.mcpserver import MCPServer

 from mealie_mcp import server

@@ -21,6 +24,26 @@ class TestAuthenticationFailures:
            server._raise_for_status(response(403, "error code: 1010"))


+def test_read_only_server_removes_all_mutating_tools():
+    test_server = MCPServer("test")
+
+    @test_server.tool()
+    def search_recipes(query: str) -> list[str]:
+        return [query]
+
+    def mutating_tool(value: str) -> str:
+        return value
+
+    for name in server.WRITE_TOOL_NAMES:
+        test_server.tool(name=name)(mutating_tool)
+
+    server._configure_read_only(test_server)
+
+    tool_names = {tool.name for tool in asyncio.run(test_server.list_tools())}
+
+    assert tool_names == {"search_recipes"}
+
+
 class TestUrlImportResponse:
    def test_slug_only_import_response_is_resolved_before_reporting(self, monkeypatch):
        recipe = {"slug": "lax-med-citron", "name": "Lax med citron", "recipeIngredient": []}