sample_my_messages

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

The description adds valuable behavioral context beyond annotations: it specifies the scope (private chats, text only, no recipients) and the intended use (style sample). Annotations already declare readOnlyHint=true and openWorldHint=true, which are consistent. The description reinforces these with concrete constraints.

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 extremely concise: two sentences that efficiently convey purpose, constraints, and differentiation. Every word adds value, with no redundancy.

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 the annotations and schema, the description provides essential context: what kind of data (user's own text messages from private chats) and its purpose (style sample). It lacks explicit mention of output format (e.g., whether it returns raw messages or aggregated stats), but given it's a sampling tool, the lack of an output schema is not critical.

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 67% with two of three parameters described (chats and min_length). The description does not add new detail about parameter meaning beyond the schema. The overall purpose context helps interpret the parameters (e.g., 'chats' is number of dialogs to sample), but per_chat lacks any description.

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 clearly states the tool collects the user's own messages from private chats for style analysis. It specifies 'raw material for describing how they write' and distinguishes itself from transcript-like tools by noting 'no recipients — this is a style sample, not a transcript.' This differentiates it from sibling tools like search_messages or get_history.

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 provides clear context for when to use the tool: for collecting a writing style sample from private chats, text only. It implicitly excludes use cases needing full transcripts or public chats. However, it does not explicitly mention alternative tools for those cases, such as search_messages for broader search.

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