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

Annotations already cover read-only/idempotent safety, so the bar is lower. The description still adds real behavioral value: exact rendered draft bytes/hash, evidence/holds, the 256 KiB refusal rule, and authentication requirement — all beyond what annotations convey.

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?

Front-loaded with purpose, then filters, then return payload, then the size/auth caveats. Dense but every clause carries information; slightly long but no filler.

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 search tool with no output schema, the description helpfully sketches the return shape (IDs, evidence, holds, draft bytes/hash) and the limit refusal behavior and auth requirement. An agent has enough to call it correctly.

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 maps the 'search' param to company/contact/email scope and mentions limit-driven narrowing for oversized replies, adding slight meaning beyond the schema's own descriptions.

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?

Specific verb (Search) + resource (user's outreach leads) with the filterable dimensions named. Distinguishes itself from siblings like list_campaign_replies or outreach_analytics by scoping to lead-level filtering.

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?

Implicitly indicates this is for finding leads via query/status/campaign filters, but offers no explicit when-to-use vs alternatives (e.g., when to prefer this over list_outreach_campaigns or add_outreach_lead). No exclusions stated.

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