Log histogram

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

Annotations already declare readOnly, idempotent, non-destructive, openWorld, so the safety profile is covered. The description adds genuinely useful behavioral detail by naming exactly what is reported (peak bucket, first/last non-empty bucket, spike onset) and flagging 'exact' counting, which the annotations do not.

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?

Two tight sentences, front-loaded with the core 'what', then the purpose clause. Little waste, though the parenthetical '(exact)' is slightly awkward placement.

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?

Given annotations carry the safety profile and the schema fully documents all 7 params, the description's job is to convey output and intent, which it does. No output schema exists, but the description summarizes the returned figures, making it reasonably complete.

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 one of the 7 parameters is already documented in the schema. The description adds nothing parameter-specific beyond the 'exact' precision note, so the 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?

States a specific verb and resource: 'Message counts over time (exact)'. Clear what it produces, but it does not distinguish itself from close siblings like count_logs or search_logs by name.

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?

'to find when a problem started' implies a usage context, which is better than nothing. However, it gives no explicit when-not guidance or named alternatives against siblings such as count_logs or compare_periods.

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