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 valuable behavioral detail beyond that: the return contents (daily fleet-wide avg score, total run count, contributing agent count) and the fact that deployment markers are unioned across agents.

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 tight sentences, front-loaded with the core purpose, then the usage cue, then the return payload. No filler or redundancy.

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 what is returned (avg score, run count, contributing agents, unioned deployment markers). Combined with a fully documented input schema, an agent has everything needed to call this correctly.

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 both parameters (days with default 30/max 365, and customerId superadmin targeting) are fully documented in the schema. The description adds no parameter-specific detail, 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 (timeline retrieval), resource (run-weighted score timeline), and scope (aggregated across ALL agents in the fleet). This clearly separates it from per-agent timeline tools like get_score_timeline in the sibling list.

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?

Gives an explicit when-to-use framing ('how is the whole fleet trending over time?') and contrasts it with the per-agent alternative ('instead of one agent at a time'), which functionally identifies get_score_timeline. It does not name the sibling tool outright, so it stops short of a full 5.

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