get_email

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

readOnlyHint=true already establishes the safe-read profile, so the bar is lower. The description adds genuinely useful context by enumerating the returned payload (sender, recipients, subject, body, schedule, delivery status) and the last_event state machine values (queued, sent, delivered, bounced, complained), which is valuable given there is no output schema.

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?

One dense sentence with the verb and scope front-loaded, followed by the field list. Nothing is wasted, though the trailing "..." in the status enumeration is slightly loose.

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 appropriately covers the return shape and the delivery-status vocabulary, which is the main thing an agent needs. It is missing only edge behavior such as a not-found id, which is a minor gap for a simple single-resource getter.

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% and the id property is already documented as "Email id returned by send_email". The description's "by id" adds no syntax, format, or sourcing detail beyond the schema, so the baseline 3 applies.

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 ("Get one email by id") and enumerates the returned fields, so it is distinguishable from the plural list_emails. It does not explicitly differentiate itself from the close sibling get_email_insights, which keeps it out of the top band.

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?

No when-to-use guidance and no mention of alternatives. The agent must infer that a single-id fetch differs from list_emails or get_email_insights purely from the word "one".

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