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

Annotations already declare destructive=true, idempotent=false and openWorld=true, so the description's added value is the confirmation protocol and the fact that 'Cannot be recalled' once sent — genuinely useful behavioral context beyond the structured hints. It loses points for referencing a '`say`' summary field that appears in neither the schema nor an output schema.

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 sentences, nothing redundant, and the most important constraint (held until confirmed, then irreversible) is front-loaded before the reader reaches the schema.

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 destructive, non-idempotent send tool with no output schema and low parameter coverage, the description covers the confirmation lifecycle well but omits who/what the '`say`' summary belongs to, thread_id semantics, and any permission or scope requirements. It is workable but not complete.

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 only 33%: only confirmation_token is documented, and neither text nor thread_id is explained in the schema. The description does not compensate — it never clarifies what text should contain or what thread_id refers to, leaving two required parameters semantically undefined.

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?

States a concrete verb and resource ('reply to an employer') and adds the perspective qualifier 'as the person', which separates it from employer-side messaging tools like message_applicant. It does not name a specific sibling alternative, so it stops short of a 5.

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 two-stage flow ('held with a summary first; sends after they say yes') is a real usage instruction, but it describes the mechanics of this tool rather than when to choose it over alternatives such as apply or draft_outreach. No exclusions or comparison to siblings are given.

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