upsell_email

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

No annotations provided. Description discloses tone ('warm, non-pushy') and a behavioral note ('does not count against your monthly draft limit'). No mention of authorization or destructive actions, but the tool is straightforward.

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 sentences with clear structure: purpose, context/statistic, timing/exception. Every sentence is necessary and well-placed.

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?

Covers use case, timing, and a behavioral trait. No output schema, but email writing tools typically don't need that. Sufficient for an agent to correctly invoke the 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?

Schema coverage is 100%, so baseline is 3. The description adds minimal extra meaning beyond schema, e.g., clarifying that 'value_hook' makes the upsell relevant. No parameter format or constraints are added beyond 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 action ('Write a warm, non-pushy email'), the audience ('a happy client'), and the context ('after a successful project'). It distinguishes from siblings like cold_pitch or project_completion_email by emphasizing existing client upsell.

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?

Explicitly states when to use ('right after delivering and getting positive feedback') and highlights high ROI. Does not explicitly mention alternatives or when not to use, but the context signals are clear enough.

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