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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows it is a safe read operation. The description adds context by disclosing the return fields and clarifying that it reports WakaTime-attributed coding time per commit, going beyond the annotation flags. No contradictions.

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 core action and parameters, then providing return value details. Every clause adds value without redundancy.

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 listing tool with five parameters (two required) and an output schema, the description covers key elements: parameters, required/optional status, special values, and return fields. It omits pagination details (e.g., page size, sorting) but that is not critical given the output schema exists. It is adequately complete for safe invocation.

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 0% (no property descriptions), so the description carries the burden. It identifies user_id and project as required (given user_id or 'current' and project name), spells out optional author, branch, and page, and explains user_id accepts the special value 'current'. This adds practical meaning beyond the bare schema types.

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 opens with 'List the commits WakaTime has recorded for one project,' clearly specifying the verb (List), resource (commits), and scope (one project per user). It distinguishes from sibling tools like 'durations' or 'heartbeats' by focusing specifically on commit records with their associated coding time.

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 provides context by stating the tool returns commit hashes, messages, authors, branches, timestamps, and coding time, and answers what has been committed and how much editor time went into it. However, it does not explicitly mention when to prefer this over sibling tools or exclude alternatives, so some guidance is implied but not fully explicit.

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