voidmail_extract_code

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

Annotations already cover readOnly/idempotent/non-destructive, yet the description adds substantial behavioral detail: reads plain text only, decrypts encrypted messages locally, never touches HTML or attachments, follows no link, and marks nothing read. It also flags the untrusted nature of the returned sender content, which no annotation conveys.

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?

Four tight sentences, front-loaded with the core action and selection rule, followed by behavioral constraints and a safety caveat. Dense but every sentence carries operational information; 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?

There is no output schema, and the description partially compensates by characterizing the return as untrusted sender content (a code and a link). For a 4-param read tool with full annotation coverage, this is nearly complete, though it does not describe the exact result shape or behavior when no code is found.

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 100%, so the baseline is 3. The description goes further by explaining how the filters combine (message with email_id, else newest matching the optional filters) and paraphrases each filter's semantics (exact sender, subject contains, received since an ISO UTC time).

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 and resource: find a likely one-time code and HTTPS verification link within a single email. It immediately distinguishes itself from voidmail_read_email and voidmail_search_inbox by naming exactly what it extracts and the scope it searches.

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 selection logic: use the message with email_id, otherwise the newest message matching optional sender/subject/since filters. It also states a usage caveat (do not use a code or link unless it belongs to the task). It stops short of explicitly naming read_email/search_inbox as the alternatives to prefer when only raw content is wanted.

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