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

Annotations already signal read-only, idempotent, safe behavior Mendes. The description adds useful behavioral context beyond them: it states the workspace scoperessed, that results include emailer_messages with emailer_steps, and that emailer_steps indicate sequence position. This is meaningful but does not discuss pagination or filtering edge cases.

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 focused sentences with no filler. The first states the action, the second clarifies the return shape, and the third redirects to the relevant sibling tool. Every sentence earns its place.

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?

The description is complete for a search tool with all-optional parameters and an output schema. It highlights the key relationship between emailer_messages and emailer_steps and names the sibling for engagement metrics. Minor details like pagination defaults and accepted filter formats are not described, but the schema and output schema largely cover those.

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 the schema already documents all eight parameters. The description itself adds no extra parameter-level meaning, but the existing parameter descriptions are adequate for basic usage. This is the expected baseline given full schema coverage.

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 names a specific verb ('Search'), a specific resource ('individual outreach emails'), and a clear scope ('already sent or scheduled from this workspace'). It distinguishes this tool from the sibling engagement tool by clarifying what it does and what it is not for.

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 an explicit use case ('Use it to see what actually went out') and names the exact alternative for per-message engagement ('get_apollo_emailer_messages_id_activities'). This is clear when-to-use and when-not-to-use guidance that an agent can act on directly.

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