signing_identities

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

With no annotations provided, the description correctly identifies this as a read-only listing operation (no side effects). The phrase 'available on this machine' adds useful context about scope, which is non-obvious from the tool name 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?

The description is a single, short, front-loaded sentence that precisely communicates the tool's purpose without any wasted words.

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 simple parameter-less listing tool, the description is largely complete. However, it could benefit from mentioning that it requires a signed developer identity to be present, or hinting at the output format (e.g., certificate details), though no output schema exists to clarify this.

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% because there are no parameters. The description adds no parameter details, but none are needed. Baseline 4 is appropriate for a zero-parameter tool.

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 uses a specific verb 'List' and a clear resource 'code signing identities available on this machine'. It clearly distinguishes itself from sibling tools like provisioning_profiles or keychain_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?

The description implies a simple listing use case, but provides no guidance on when to use this tool vs. alternatives like provisioning_profiles for inspecting signing identities, nor any conditions (e.g., prerequisite of having a development team set up).

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