> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pidgeon.health/llms.txt
> Use this file to discover all available pages before exploring further.

# MCP Tool Catalog

> The exact free, community, and Pro tool split the Pidgeon MCP server exposes — matching the checked-in community catalog and the Bridge-advertised roster.

The server ships **22 tools**: 13 free and 9 Pro. Which ones register depends on the [transport mode](/mcp/overview#two-transport-modes). This page is the human-readable companion to the generated `MANIFEST.md` and the checked-in community catalog; the live, machine-readable roster for your session is always `pidgeon://version`.

## Community tools (CLI mode)

With `PIDGEON_MODE=cli` — no account, no Bridge — the server registers **exactly these eleven** tools: the ones the free CLI's command catalog can service end to end. Nothing else appears; a Pro tool never materializes from a client-side label.

| Tool                   | What it does                                                                                                          |
| ---------------------- | --------------------------------------------------------------------------------------------------------------------- |
| `generate_message`     | Generate synthetic HL7 v2 / FHIR R4 test messages. Deterministic by `seed`.                                           |
| `validate_message`     | Validate HL7 v2 / FHIR R4 / NCPDP against the spec, with a conformance score and per-field findings.                  |
| `explain_message`      | Plain-English breakdown of a message's segments and fields.                                                           |
| `explain_error`        | Turn a validation finding into a root cause and a suggested fix (no model required).                                  |
| `deidentify_message`   | On-device de-identification of a single message.                                                                      |
| `lookup_code`          | Look up a code in an embedded code system (ICD-10, LOINC, and more).                                                  |
| `get_segment_spec`     | Field-by-field spec for an HL7 segment.                                                                               |
| `manage_data_packages` | List and install reference data packages.                                                                             |
| `search_artifacts`     | Search local starter recipes, installed recipes, and data packages.                                                   |
| `pidgeon_status`       | Local environment and capability diagnostics.                                                                         |
| `describe_tool`        | Return the full contract for any tool by name — free and uncapped, and it describes Pro tools without unlocking them. |

<Note>`generate_message` in CLI mode is single-patient and volume-capped, with graceful degradation as you approach the cap — never a hard failure that breaks an agent loop.</Note>

## Free tools added in Bridge mode

With `PIDGEON_MODE=bridge` and a running desktop app, the Bridge advertises the full free tier — the eleven community tools plus these two (their substrate runs in the Bridge, so the CLI alone can't service them):

| Tool              | What it does                                                      |
| ----------------- | ----------------------------------------------------------------- |
| `semantic_review` | Advisory clinical-sense review of a message (HITL, never blocks). |
| `clinical_check`  | Deterministic clinical-coherence checks.                          |

<Note>NCPDP validation through `validate_message` depends on the license-gated `ncpdp-script` package (NCPDP membership required). See [Message Generation](/post/message-generation#ncpdp-script-2017071).</Note>

## Pro tools

These nine are server-advertised only after authentication, for a resolved subscription tier. They require a [Pidgeon account](/getting-started/account) with an active subscription — the **Agentic Seat** (\$49/mo per developer or agent seat), or usage-metered credits.

| Tool                     | What it does                                                                |
| ------------------------ | --------------------------------------------------------------------------- |
| `generate_population`    | Generate an FK-safe synthetic population at scale (Flock).                  |
| `population_status`      | Check the status of a running population job.                               |
| `run_workflow`           | Run a multi-step, one-patient clinical scenario (admit → labs → discharge). |
| `diff_messages`          | Field-level diff between two messages or environments.                      |
| `analyze_vendor_pattern` | Learn and save a reusable vendor profile from sample traffic.               |
| `refine_hl7_segment`     | AI-assisted in-place edit of an HL7 segment (on-device by default).         |
| `send_message`           | Deliver messages to an SFTP or Mirth pickup folder.                         |
| `conform`                | Probe a FHIR endpoint against an Implementation Guide (CMS-0057-F).         |
| `loft_status`            | Read Loft interface-monitoring status (Loft is entirely paid).              |

## How the split is enforced

The community set is a checked-in, fail-closed allowlist — registration by reflection or filesystem discovery is forbidden for the public composition. In Bridge mode the server registers exactly what the Bridge advertises for your tier; when a tier changes, the advertisement refreshes and newly entitled tools unlock. There is no way to surface a tool the active composition doesn't include.

## Next steps

* [MCP Server overview](/mcp/overview) — install, transport modes, prompts, and resources
* [Your Pidgeon account](/getting-started/account) — plan and entitlements