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

Despite annotations already marking this as destructive and non-read-only, the description adds valuable behavioral context: keys are 'CALL-ONLY', capped at a daily MESH spend, and cannot 'list, buy, refer, or mint further keys'. These constraints are not in the annotations, so the description enriches the agent's understanding of side effects and limitations.

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 sentences, front-loaded with the primary verbs and resource. The first sentence covers all three actions plus constraints; the second adds safety framing. No redundant or filler content. Every word earns its place.

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?

For a 5-parameter tool with no output schema, the description covers the actions, security restrictions, and spending cap. It does not mention return formats or how to handle the required 'action' field, but these are implied by the actions themselves and the schema. A small gap, but overall quite complete for tool selection.

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 high (80%), so the baseline is 3. The description adds meaning by mapping the trio 'Mint, list, or revoke' to the action enum, and explaining 'CALL-ONLY' and 'daily MESH spend' which clarify the semantics of 'allow' and 'daily_cap'. This goes slightly beyond the schema descriptions.

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?

The description opens with 'Mint, list, or revoke CALL-ONLY delegated keys', a specific verb+resource pair. It clearly distinguishes itself from sibling mesh tools by noting the sub-key 'can't list, buy, refer, or mint further keys', which differentiates this delegation tool from other MESH operations.

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 phrase 'Safe agent-hires-agent' provides a clear use case for delegating limited capabilities to a sub-agent. It gives context for when to use the tool (hiring agents with restricted powers) but does not explicitly name alternatives or state when not to use it. Still, the intended usage scenario is evident.

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