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

Annotations already declare readOnlyHint=true, openWorldHint=true, destructiveHint=false, so the safety profile is covered. With no output schema, the description carries the return-shape burden and does so well: it names the breakdown dimensions plus cumulative total and daily average, and discloses the conditional behavior that project+branches additionally yields per-branch and per-file entities. Auth/rate-limit behavior is not mentioned.

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?

Three sentences, no filler, and the payload/return structure is front-loaded before the input mechanics. The trailing endpoint string 'GET /users/current/summaries' is useful for routing but is the one element that serves the implementer more than the caller.

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 an 8-parameter, zero-required read tool with no output schema, the description covers what the call returns, how to specify the window, and the non-obvious project+branches interaction. The remaining parameters are fully documented at 100% schema coverage, so nothing an agent needs to invoke it correctly is missing.

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 100%, which sets a baseline of 3, but the description adds meaning the schema does not: project combined with branches produces extra per-branch and per-file entities, and start/end are presented as one option against a named range. The remaining parameters (timeout, timezone, writes_only) are left entirely to 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?

States a specific verb and resource ('coding activity as one summary per day for a date range') and enumerates what the summary contains: grand total, breakdowns by project/language/editor/OS/category/dependencies/machine, cumulative total, daily average. It does not explicitly distinguish itself from siblings such as wakatime_get_stats or wakatime_get_org_dashboard_summaries, so an agent must infer the boundary.

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?

'Give start and end, or one named range' tells the agent how to parameterize, but never says when this tool is the right choice versus wakatime_get_stats, wakatime_get_durations, or the org dashboard summary variants. Usage is implied by the scope statement rather than stated, and no prerequisites or exclusions appear.

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