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

Annotations already cover read-only, idempotent and non-destructive behavior, so the bar is lower. The description still adds real context beyond them: ordering ("newest first"), that deleted agents are excluded, and the key-based scoping. These are concrete traits an agent cannot infer from the annotations alone.

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 with the scoping constraint front-loaded and no filler. The opening line merely repeats the title verbatim, which is slight redundancy, but the remaining content is efficient.

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 exists, so the description usefully covers return characteristics: the `id` field maps to the `agentId` used by agent endpoints, ordering, and deleted-agent exclusion. It does not mention pagination or result limits, which is the only notable gap for a list tool.

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?

The tool takes zero parameters, so the baseline is 4. There is nothing to document, and the description correctly adds no parameter claims it cannot support.

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 ("List") and resource ("agents") plus a precise scope ("this key can act on"). This cleanly separates it from siblings like get_agent (single agent) and list_agent_members (members within an agent) without the agent needing to open any schema.

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 description clarifies the result scope ("every agent, or only those on the key's agent list") but never states when to prefer this over get_agent or list_agent_members. Usage is implied by the verb rather than explicitly guided, and there are no exclusions.

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