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

Annotations declare the safety profile (idempotent, non-destructive, openWorld), and the description goes well beyond them by disclosing a real side effect: a detected reply moves the CRM lead to the 'replied' stage, which explains why readOnlyHint is false despite the 'get' name. It also documents that reply text is not returned and gives actionable recovery guidance for the 'approved'/'failed' states (retry by approving again).

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 and side effect before the long status enumeration. The status glossary is dense but earns its place since there is no output schema to carry the possible return values. Slightly heavy, but every segment carries information.

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?

With no output schema, the description correctly assumes responsibility for documenting the returnable statuses, including non-obvious ones like pending_approval and provider-error 'approved'. Combined with annotations it covers safety, side effects and return values. The only real gap is the undocumented outreach_id parameter.

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 0%, so the lone parameter carries no structured documentation, and the description never explains what outreach_id is or where to obtain it. It only indirectly implies the tool acts on 'one e-mail'. With coverage this low the description should compensate and does not.

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 specific verb+resource: 'Refresh one e-mail's status and return it' — the agent immediately knows it fetches current state for a single outreach. It is clearly distinguishable from siblings like list_email_outreach (bulk list) and approve_message/cancel_email (mutations). The added note that reply text is not fetched further sharpens the boundary against list_lead_messages.

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?

Usage is implied rather than stated: the tool refreshes and returns a single email's status, and the exclusion 'Reply text itself is not fetched' hints that another tool covers reply bodies. However, it never names an alternative nor says when an agent should call this versus list_email_outreach when it wants status for many emails. Adequate but with a clear routing gap.

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