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

Annotations already establish read-only, idempotent, non-destructive, open-world behavior. The description adds useful context by disclosing the WakaTime personal OAuth token requirement and the per-day breakdown return shape, though it does not discuss rate limits, pagination, or timezone effects.

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 a single front-loaded sentence that states the action, required date range, return content, and auth requirement without filler. There is minor redundancy between 'daily coding summaries' and 'per-day breakdowns', but it remains efficient.

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?

It covers the mandatory invocation path well: user_id, start/end date format, token requirement, and summary return content. Because an output schema exists, return details need not be fully explained, but the description still leaves several optional filtering parameters unexplained for a nine-parameter 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 description coverage is only 11% across nine parameters, so the description must carry most parameter meaning. It explains start/end, date format, and the _apiKey auth requirement, but leaves project, timeout, branches, timezone, writes_only, and user_id semantics largely 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?

States a specific verb and resource: fetch WakaTime daily coding summaries for a user over a date range, with a clear return breakdown. It is distinguishable from most siblings by the 'daily summaries' framing, but it does not explicitly contrast itself with nearby tools like stats, durations, or commits.

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?

It specifies that start and end are required and gives the date format, which implies how to invoke the tool. However, it provides no explicit guidance on when to choose summaries over siblings such as stats, durations, or commits, and no exclusions or alternative-routing advice.

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