Report an outcome

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

With no annotations, the description carries the full burden. It does disclose one meaningful side effect — a bounce marks the address undeliverable for future checks — which is genuine behavioral value. However, it omits whether reports are idempotent, whether they override prior events, and any auth/permission requirements for a mutation tool.

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?

Two tight sentences with the action front-loaded and the consequence immediately after. Slight waste in re-listing enum values the schema already declares.

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 mutation tool with no annotations and no output schema, the description covers what to report and one downstream effect. It still leaves duplicate-report behavior, permission needs, and whether reporting triggers other workflows (e.g., sequence suppression) unexplained.

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 only 33%, but the description restates the `kind` values already defined by the schema enum and says nothing about the required `email` field or the optional `detail` field. It adds little beyond the schema and does not compensate for the coverage gap.

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 (report) and resource (outcome of a sent email), and enumerates the accepted outcome kinds. An agent can tell this is a write-back of delivery events, though it does not explicitly distinguish itself from sibling readers like email_status or check_lead.

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?

"what happened after sending" implies the usage window, but no alternatives are named and no exclusions or prerequisites are given. It is adequate context without routing guidance.

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