overview

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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds useful behavioral context by enumerating the computed outputs, including unusual details such as PageRank-based central symbols and resolution rates, going beyond the structured hints.

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?

A single, front-loaded sentence delivers the usage instruction first, then the output summary. Every clause adds information, with no filler or redundant restatement of the tool name.

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 input schema and no output schema, the description carries the full burden of explaining what the tool returns; it does so by listing the key output dimensions. For a zero-parameter overview tool, this is complete and actionable.

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?

The tool takes zero parameters, so no parameter documentation is required. The description clarifies that the tool operates over the entire repository, which is the only meaningful semantic needed.

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 identifies the tool's purpose: a first-call repository overview that reports size, languages, call-graph shape, overall score, and finding count. It uses a specific resource ('repository') and differentiates itself from the more targeted sibling tools by being the entry-point summary.

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 first phrase 'Call first in an unfamiliar repository, before planning any change' explicitly states when to use this tool. This positions it as a preface to the more specific sibling tools and gives an agent a clear decision rule.

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