Coverage Gap Report

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

Annotations already declare readOnlyHint=true, so no destructive actions. The description adds value by detailing the output structure (coverage matrix with entries, grade, best match, source type needed) and the behavioral purpose of identifying gaps before report building. No contradiction.

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 two sentences, front-loaded with the main purpose. The second sentence is dense but well-structured, covering output and usage without fluff. Efficient and clear.

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 2 parameters (1 required), no enums, and an output schema present, the description provides good context. It explains the output and usage sequence, which is sufficient for the tool's complexity.

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 100% with both parameters described. The description adds a concrete example for 'themes' ('opium, gin, gambling, racing') and notes 'archives' is optional, which matches schema. This adds minor value but doesn't significantly extend beyond the schema.

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 function: given themes, report evidence coverage. It specifies the output (coverage matrix with entries, grade, best match, source type) and distinguishes from sibling tools by stating it should be used before archive_report_brief or brief_forensic.

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 explicitly says 'Use this BEFORE building an archive_report_brief or brief_forensic to know where the evidence is strong and where gaps will appear.' It also explains the benefit: preventing building reports that ignore gaps. While it doesn't explicitly list when not to use, the usage context is very clear.

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