# get_flag_registry

[SUPPORT] 45802b67 — scan a source tree for os.environ.get(...) / os.getenv(...) call sites (AST-based, not regex) and return a flat inventory of every config flag the codebase reads: {flag_name, file, line, default}. Only call sites where the flag name is a STRING LITERAL first argument are included — dynamic names (a variable, f-string, etc.) are skipped gracefully rather than erroring. The default is best-effort literal-eval'd from the second positional arg (or a default= keyword); a non-literal default evaluates to null. Useful for auditing config drift — 'what env flags exist, where are they read, what do they default to' — without grepping by hand. Returns {repo_root, flags:[...], count, unique_flag_names:[...], unique_count}. A missing/empty tree returns an empty flags list, never an error.

Agent View of the PolicyLayer registry record for `get_flag_registry`. HTML page: https://policylayer.com/tools/io-github-ajc3xc-meridian/get-flag-registry

## Facts

- Tool: `get_flag_registry`
- Server: Meridian (`@meridianmcp/mcp`) — https://policylayer.com/tools/io-github-ajc3xc-meridian.md
- Install: `npx -y @meridianmcp/mcp`
- Homepage: https://github.com/meridianmcp/Meridian
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 1
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `root_dir` | string | no | Absolute path to the source-tree root to scan recursively (vendored/build/cache dirs like node_modules/.git/dist/__pycache__ are pruned). Defaults to the server |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "get_flag_registry",
    "arguments": {}
  }
}
```

## Why get_flag_registry is rated Low

This tool performs static analysis of source code to extract metadata about environment variable access patterns. It has no side effects: it does not create, modify, delete, execute code, move money, or trigger external operations. It purely retrieves and inventories information from existing code. The 'best-effort' literal-eval and skipping of dynamic names confirms passive analysis.

From the tool's own definition: "Tool description explicitly states it 'scan[s] a source tree for... and return[s] a flat inventory' of config flags. The verb 'scan' and 'return' indicate retrieval/query with no modifications."

Risk signals: Bulk/mass operation — affects multiple targets

## Use case

AI agents call get_flag_registry to retrieve information from Meridian without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Meridian:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "get_flag_registry": {}
  }
}
```

## Other tools on Meridian (174)

- `archive_decision` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/archive-decision.md
- `batch_mutate` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/batch-mutate.md
- `claim_sprint_item` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/claim-sprint-item.md
- `clear_capability_profile` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/clear-capability-profile.md
- `clone_profile_layer` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/clone-profile-layer.md
- `delete_custom_hook` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-custom-hook.md
- `delete_note` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-note.md
- `delete_sprint_item_pointer` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-sprint-item-pointer.md
- `fan_out_sprint_items` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/fan-out-sprint-items.md
- `purge_ai_log` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/purge-ai-log.md
- `record_handoff_correction` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/record-handoff-correction.md
- `release_docx_region_claims` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/release-docx-region-claims.md
- `request_hitl` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/request-hitl.md
- `reset_plugin_override` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/reset-plugin-override.md
- `reset_profile_layer` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/reset-profile-layer.md
- `complete_wave_gate` — Execute — https://policylayer.com/tools/io-github-ajc3xc-meridian/complete-wave-gate.md
- `execute_batch` — Execute — https://policylayer.com/tools/io-github-ajc3xc-meridian/execute-batch.md
- `prospect_symbol` — Execute — https://policylayer.com/tools/io-github-ajc3xc-meridian/prospect-symbol.md
- `run_verification` — Execute — https://policylayer.com/tools/io-github-ajc3xc-meridian/run-verification.md
- `start_session` — Execute — https://policylayer.com/tools/io-github-ajc3xc-meridian/start-session.md
- `analyze_model_efficiency` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/analyze-model-efficiency.md
- `analyze_sprint` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/analyze-sprint.md
- `batch_read` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/batch-read.md
- `find_outputs_by_source` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/find-outputs-by-source.md
- `find_similar_equation` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/find-similar-equation.md
- `find_similar_figure` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/find-similar-figure.md
- `find_similar_table` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/find-similar-table.md
- `find_symbol_usages` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/find-symbol-usages.md
- `get_agent_instructions` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/get-agent-instructions.md
- `get_blog_posts` — Read — https://policylayer.com/tools/io-github-ajc3xc-meridian/get-blog-posts.md
- …and 144 more: https://policylayer.com/tools/io-github-ajc3xc-meridian.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-ajc3xc-meridian · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-ajc3xc-meridian