Signing Setup Distribution

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

Annotations already declare destructiveHint=true, openWorldHint=true, and non-idempotent, so the safety profile is covered structurally. The description adds genuinely new context—'live write', 'needs human approval', and installation into a *temporary* keychain (implying ephemeral, non-persistent state). It stops short of describing the two-call approval retry mechanics, which the schema handles instead.

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 labeled fragments (action, Use when, Returns) with zero filler and the destructive/approval caveat front-loaded in the first sentence.

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?

An output schema exists, so the 'Returns' line is redundant rather than load-bearing, but the description covers purpose, alternative routing, and the destructive/approval nature of a risky write. The only real gap—the exact approval_id retry sequence—is already covered by the schema.

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% and the single approval_id parameter is thoroughly documented in the schema, including the out-of-band human approval flow. The description adds no parameter detail; baseline 3 applies since the schema does all the work.

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 concrete verb and resource ('Create a distribution certificate and install it into a temporary keychain') plus material scope details (WWDR included). An agent can distinguish it from signing_create_profile and from the higher-level testflight_ship without opening schemas.

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?

'Use when: hand-running signing steps; testflight_ship does this for you' explicitly names the trigger condition and the alternative tool that subsumes it. This is a model routing instruction, not vague guidance.

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