smtp_forward_message

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

With no annotations, the description carries full responsibility for behavioral disclosure. It only says 'Forward an existing message via SMTP' and does not disclose how the original is fetched, how the body is handled, what side effects occur (sending a new email), or any failure modes. Behavioral traits are left to the schema or the agent’s guesses.

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?

The description is a single, front-loaded sentence with no repetitive or unnecessary words. It efficiently says what the tool does without restating the name verbatim. The one-sentence structure is ideal for clarity and quick scanning.

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 schema is rich (100% coverage, detailed parameter descriptions) and an output schema exists, so return values need not be described. However, the description lacks usage context (when to use vs smtp_reply_message, prerequisites, and consequential behavior), which is not fully compensated by the parameter descriptions. It is minimally complete but not genuinely helpful for a human–agent decision.

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?

The input schema has 100% parameter coverage with detailed descriptions for each field. The description itself adds no semantic meaning beyond the schema, which is sufficient at the baseline level for a fully-covered schema. Nothing is repeated or expanded in the description text, so no bonus is earned.

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 states a specific action ('Forward') and resource ('existing message via SMTP'), which is sufficient to distinguish it from smtp_send_message or smtp_reply_message. However, it does not explicitly call out or differentiate from these siblings, so it lacks the explicit cross-tool comparison that would earn 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 description gives no guidance on when to choose this tool over alternatives. It does not mention conditions, prerequisites, or exclude smtp_send_message / smtp_reply_message. Some schema parameters hint at alternatives, but the description text itself offers no usage direction, which is a clear gap given the sibling wave.

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