check_match

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

Annotations already declare readOnlyHint=true and openWorldHint=false. The description adds real behavioral context beyond that: the fact-by-fact comparison method, name-variant handling, Julian calendar and rounded-age tolerance, and a full verdict taxonomy with a threshold for 'confirmed'. It omits nothing critical for a pure local computation.

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?

Two sentences, front-loaded with the core question and a tight parenthetical on special handling, then the verdict list. No filler; every clause earns its place.

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 an output schema present, the description need not explain return values, yet it helpfully enumerates verdicts anyway; annotations cover the safety profile. The remaining gap is the unexplained 'lang' and 'year_tolerance' semantics, which is minor for this comparison tool.

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 coverage is 50%: 'known' and 'found' are described, but 'lang' and 'year_tolerance' have no descriptions in the schema. The description hints at tolerance behavior (Julian/rounded-age) without mapping it to 'year_tolerance', and never explains what 'lang' controls. Adequate but not compensating for the coverage gap.

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 question ('Is the person in a found record ours?') that names the exact verb (compare fact by fact) and resources (known person vs. found record), then enumerates the output verdicts. This is clearly distinguishable from DNA-based siblings like dna_match and kinship.

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?

Implies the usage context (comparing a known person against a discovered record to decide if it is the right person) and gives useful decision criteria ('2+ independent facts beyond the name' = confirmed). However, it names no alternatives and states no when-not-to-use conditions, e.g. when to prefer dna_match.

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