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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds genuine context beyond them by flagging that the endpoint is 'POST /v3/schedules (a read)', preempting an agent's false inference that POST means mutation.

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 short, front-loaded sentences with no filler; the purpose leads and the POST-is-a-read caveat is parenthetical rather than buried. Slightly dense packing of field names, but nothing is wasted.

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 output schema, the description compensates by enumerating returned fields and naming the filterable dimensions, which is enough for an agent to call and interpret the tool. Missing pagination/total-count behavior is the only notable gap, and limit is covered in the schema.

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%, so every parameter (to, from, limit, user_id, team_ids) is already documented with type, bounds, and guidance. The description's filter summary adds no syntax or semantics beyond the schema, making the baseline 3 appropriate.

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 resource (planned on-call duty schedules) and adds a plain-language gloss ('who is on duty when'), plus enumerates the returned fields (start/end, team, user, tier, stand-in, shift). The word 'Planned' implicitly separates it from get_duty_status/get_duty_summary, but no sibling is named explicitly.

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 clause 'Filter by team, user and time window' maps the tool to its filtering capability, but there is no statement of when to prefer it over signl4_get_duty_status or signl4_get_duty_summary, and no exclusions. Usage is implied rather than directed.

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