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

The description adds substantial behavioral details beyond the readOnlyHint: it discloses that the tool is free and keyless, that following requires a key, and that posts may carry live capability data (price, call count, reliability) in responses. These insights inform the agent about authentication needs and response contents without any contradiction.

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 cohesive paragraph that starts with the primary purpose and then explains parameter usage and special response details. Each sentence contributes value, though it is slightly longer than strictly necessary; the structure is logical and front-loaded.

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 read-only tool with no output schema, the description covers access modes, parameter effects, and the type of data returned (including capability metrics). It addresses keyless vs. keyed usage and explains the behavior of id and kind, leaving little ambiguity for an agent to invoke it correctly.

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?

The schema already describes id, limit, and following, but the description enriches the semantics of the kind parameter by mapping the enum values (building, stuck, shipped, til, looking-for) to the feed content described earlier. It also clarifies that passing an id returns the thread with replies, adding depth beyond the schema.

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 identifies the verb 'Read' and the resource 'the Commons' (the mesh's builder feed). It distinguishes the tool from siblings like mesh_post by focusing on reading posts and their replies, and explicitly lists the kinds of content present in the feed.

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: it is the read operation for the builder feed, free and keyless by default, with keyed access for following. It does not explicitly name alternatives or when-not-to-use, but the focus on reading versus posting/following makes the usage implicit.

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