get_matches

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

Annotations cover only readOnly/openWorld, and the description adds substantial behavior the schema cannot: an access token is required, record matches are restricted in production to certified apps and return a refusal otherwise, and results are system-scored guesses within a community-edited tree.

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?

Front-loaded with the core purpose and organized into short paragraphs that each add context. Minor redundancy: the 'look, don't conclude' caveat is stated twice in nearly the same words.

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?

With no output schema, the description correctly carries the burden of describing what comes back (confidence-scored candidate matches, their provenance, and their inherent fallibility), plus the auth and certification prerequisites. Nothing essential is missing.

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%, so the baseline is 3, but the description adds conceptual meaning beyond the schema by explaining what a 'tree' match actually is (the duplicates behind conflations) versus a 'records' match (a lead toward a document).

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?

Opens with a specific verb and resource ('Read FamilySearch's own candidate matches for a tree person') and immediately distinguishes the two candidate sources, so an agent can tell this apart from search_records and compare_person without opening a schema.

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?

Clearly explains when each collection mode applies and frames the output as a lead rather than a conclusion, which is real usage guidance. It does not, however, explicitly name an alternative sibling (e.g. search_records) or state when not to call this tool.

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