Read message thread

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

The note 'opening a thread may mark it as read in ProBo' is genuinely useful side-effect disclosure that annotations cannot express, but it conflicts with readOnlyHint=true (marking read mutates ProBo state) without acknowledging that tension. Otherwise no auth requirements, rate limits, or thread-size caveats are given.

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 short sentences, front-loaded with the core action and output shape, followed by the caveat. No padding, though the trailing note could be tightened.

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?

An output schema exists, so return-format explanation is rightly omitted, but the definition leaves the lone required parameter undocumented and provides no selection context against 12 sibling tools. Adequate but with clear gaps.

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?

Only one parameter (message_id) exists and schema description coverage is 0%, so the schema contributes nothing beyond the field name. The description implies message_id selects a thread but adds no format, source, or where-to-obtain-it details, leaving the parameter semantics thin.

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 and resource with scope: 'Get a full message thread: every reply as Markdown, plus attachment paths.' This distinguishes it from list_messages, but the description never names the sibling explicitly, so the differentiation is implicit rather than stated.

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?

There is no when-to-use guidance, no prerequisites, and no routing to alternatives. The note about ProBo read-state is a side-effect warning, not usage guidance, so an agent must infer that this is the tool for a known message_id rather than a search/list tool.

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