Fathom MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=true, and idempotentHint=true, covering safety and behavior. The description adds valuable context beyond this: it explains how duration is calculated ('from recording start to end time'), team breakdown logic ('based on recorder's team'), and defines 'external' meetings ('one or more external participants'). This enhances understanding without contradicting annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with clear sections (Args, Returns, Examples, Notes) and front-loaded purpose. It's appropriately sized for a tool with 4 parameters and no output schema, though some redundancy exists (e.g., parameter descriptions in both schema and description). Most sentences earn their place by providing examples or clarifying notes.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (analytics with filtering), rich annotations (4 hints), and 100% schema coverage, the description is mostly complete. It explains key behavioral aspects (e.g., calculation methods) and provides examples. However, without an output schema, it could benefit from more detail on return value formats or limitations, but the Returns section partially compensates.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with each parameter well-documented in the schema (e.g., 'Filter meetings created after this ISO 8601 timestamp'). The description repeats parameter names and adds minimal extra semantics (e.g., examples for 'created_after' and 'teams'), but doesn't significantly enhance meaning beyond what the schema provides. With high schema coverage, the baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Get analytics and statistics about your Fathom meetings' and specifies what it calculates ('aggregate statistics about your meetings including duration metrics, team breakdowns, and internal vs external meeting ratios'). It distinguishes from siblings like 'fathom_list_meetings' by focusing on analytics rather than listing. However, it doesn't explicitly differentiate from 'fathom_participant_stats' which might also provide statistical insights.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides implied usage through examples (e.g., 'All time stats', 'This month', 'Sales team'), suggesting when to use this tool for aggregated analytics. However, it lacks explicit guidance on when to choose this over alternatives like 'fathom_list_meetings' for raw data or 'fathom_participant_stats' for participant-focused stats. No when-not-to-use scenarios or prerequisites are mentioned.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.