hotspots

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

Annotations only declare readOnlyHint=true, so the description carries extra weight and delivers: it discloses the ranking formula, that renames are followed, that test files are excluded by default, and that output is capped at <=1200 tokens. That is real behavioral context an agent could not infer from the annotation.

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?

Roughly forty words, front-loaded with the core definition so the reader learns what a hotspot is first. The telegraphic fragments ('renames followed', '<= 1200 tokens') are terse but each clause carries information; nothing is padding.

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?

For a read-only tool with no output schema, the description covers the metric, defaults, exclusions, and token budget, but leaves the return shape vague — 'per file' does not tell the agent what fields to expect or how the score is presented, and 'limit' is never tied to the output.

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 0%, so the description must compensate. It explains 'since' (a ref or a date such as '6 months ago', defaulting to 1 year) and 'include_tests' (test files omitted unless set), but says nothing about what 'limit' controls, leaving one of three parameters undocumented.

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 names the resource (files) and the specific behavior it surfaces — files that change often and hold much code — plus the ranking metric (commits x lines inside methods). It is concrete enough for an agent to know what comes back, though it never names or distinguishes itself from siblings like diff_impact or repo_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?

There is no statement of when to reach for this tool versus the alternatives in the sibling list. The only usage-adjacent text is the default window and the test-file exclusion, which are behavior, not selection guidance.

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