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

Annotations already declare readOnlyHint/non-destructive, and the description adds real behavioral context: ranking basis (median engagement), per-slot sample size, timezone semantics, and the insufficient-data degradation path. It stops short of stating anything about latency or caching, so not a 5.

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?

Front-loaded with the user-facing question and the return shape, then the exclusion. Every sentence carries distinct information; no filler.

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?

No output schema, but the description compensates well by describing the returned slots, their ranking metric, and their sample-size field. The only gap is that it doesn't mention what the response looks like when the platform has no data for the requested window beyond the generic insufficient-data note.

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 100% and the schema already documents platform, limit defaults/max, period presets, and the start_date/end_date override. The description restates limit's default/max and the custom-range behavior, adding little beyond the schema, so baseline 3 applies.

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?

Specific verb+resource: returns day-of-week and hour slots ranked by median engagement for a given platform. It explicitly distinguishes itself from the posting-schedule siblings by naming list_queue_schedule and add_queue_times.

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?

Opens with the exact user questions it answers ("when should I post?", "when does my audience engage?") and closes with an explicit when-not and the alternative tools to use instead for schedule changes.

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