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

With no annotations provided, the description carries the full burden and does well: it discloses that the tool returns the subject and body, performs no sending, and that sending happens later from the user's mailbox. This is important behavioral context that an agent needs before invoking the tool.

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 short, purposeful sentences: the action comes first, then the output and non-sending behavior, then the requirement. Every sentence earns its place and the structure is front-loaded.

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?

Since there is no output schema, the description correctly explains the return value (subject and body) and the non-sending behavior. It leaves 'page_title' and 'sender_name' semantically unexplained, but those are optional and the core invocation path is well-covered by the description and required parameters.

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 67%, so the schema already documents most parameters. The description reinforces the meaning of 'hook' as the reason the prospect would link and 'prospect_url' as the target page, but it adds no new meaning for the undocumented optional params 'page_title' and 'sender_name'. Baseline 3 is appropriate.

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 ('Write') and clearly identifies the resource and result: one outreach email for one prospect, returned as subject and body. It is clearly distinguishable from sibling discovery and verification tools, despite not naming them explicitly.

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 gives clear context: use this when you need to draft a single outreach email with a personalized reason. It also provides an important exclusion ('sends nothing') and a prerequisite ('paid Mentionry plan'), which helps the agent decide when and whether to invoke it.

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