send_email

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

No annotations are provided, so the description carries the full behavioral burden, and it discloses almost nothing: not whether the message is actually dispatched externally, who the sender is, whether sends are rate-limited, or whether the action is irreversible. The single ':return: Confirmation message' line is the only behavioral hint, and an output schema already exists.

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 the purpose sentence, then one line per parameter; there is no filler. The Sphinx-style ':param:' markup is docstring residue rather than agent-facing prose, which costs a little readability but no real length.

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 tool with real external side effects and zero annotation coverage, the description is thin: nothing about delivery behavior, sender identity, permissions, or failure modes. An output schema does exist, so the return-value line being minimal is acceptable, but that does not offset the missing behavioral context.

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% (properties carry only titles), so the description must compensate, and it does: all four parameters are documented with meaning beyond the schema — notably that html flags whether body is HTML. The explanations are terse (e.g. no format hints for to_emails) but semantically complete.

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 first line states a specific verb and resource ('Send an email'), which is enough to distinguish it from every sibling tool in the set, none of which are email-related. It is clear but not differentiated from any alternative, since no alternative exists.

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 when-to-use guidance, no prerequisites, and no exclusions. There is no mention of when email is the appropriate channel versus e.g. create_ticket or schedule_meeting, even though those siblings compete for the same notification-style intent.

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