set_email_signature

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

With no annotations provided, the description carries full burden and does well by disclosing key behaviors: the signature is automatically appended to sent emails, photo_url auto-uploads local files, and it returns a confirmation with preview. It doesn't cover permissions, rate limits, or error handling, but provides substantial operational context.

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 well-structured and front-loaded with the core purpose, followed by organized sections for args, returns, and examples. Every sentence adds value, with no redundancy, making it efficient despite its comprehensiveness.

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?

Given the tool's complexity (9 parameters, no annotations, but with output schema), the description is complete. It covers purpose, usage, parameters, behavior, and examples. The output schema handles return values, so the description appropriately focuses on input and operational context.

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 0%, so the description must compensate fully. It provides detailed semantics for all 9 parameters, including examples, optional/default values, and behavioral effects (e.g., photo_url triggers HTML signature). This adds significant meaning beyond the bare schema.

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 clearly states the tool's purpose with specific verbs ('create and save') and resource ('professional email signature'), distinguishing it from sibling tools like get_email_signature or list_email_signatures. It explains the outcome ('automatically appended to all sent emails') and differentiates between text and HTML signatures based on optional parameters.

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 provides clear context on when to use this tool (to create signatures that will be appended to emails) and implies usage through parameter descriptions (e.g., photo_url creates HTML signatures). However, it doesn't explicitly state when NOT to use it or name alternatives like get_email_signature for retrieval, though the distinction is clear from purpose.

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