set_read_state

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

Annotations already declare idempotentHint=true, readOnlyHint=false, and destructiveHint=false. The description's 'idempotently' repeats the annotation, and the word 'one' adds minimal scoping context. It does not disclose additional behaviors like auth requirements or response semantics, but it does not contradict the annotations either.

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 concise sentence with no filler and front-loaded purpose. However, it is almost too sparse, functioning as a fragment rather than a complete thought, which slightly reduces clarity despite its efficiency.

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?

Given 5 required parameters, including IMAP-specific uidd_validity concepts, no schema descriptions, and the existence of a batch sibling, the description is insufficient. It does not explain how to identify the message or when to prefer the single vs batch variant, leaving the tool under-documented for reliable use.

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% and the description explains none of the 5 parameters. Terms like uid_validity and mailbox are left undefined, so the description fails to compensate for the sparse schema and offers little meaning beyond parameter names.

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 'Set one read state idempotently.' uses a specific verb 'Set' and a clear resource 'read state', making the operation obvious. The word 'one' distinguishes it from the batch sibling set_read_state_batch, although it does not explicitly name the alternative, so it falls short of perfect sibling differentiation.

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 guidance is given on when to use this tool versus set_read_state_batch or set_star. The singular 'one' implies a single-message use case, but there is no explicit context about prerequisites, exclusions, or alternatives, leaving the agent to infer usage.

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