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

Beyond the annotations, the description reveals an important behavioral trait: calling it twice does not replace an existing mesh but returns the existing one. This materially shapes an agent's expectations and is more than the annotations alone provide.

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?

Three tightly written sentences, each earning its place: what the tool does, when to use it versus the join sibling, and what happens on repeated calls. The key scoping fact is 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 one-parameter tool with an output schema and sibling guidance, the description covers selection, invocation, placement in the mesh lifecycle, and idempotency. Nothing an agent needs to call this tool correctly is missing.

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 100%, and the single optional label parameter is already well described in the schema as the human name for this machine. The description adds no new parameter detail, so the baseline of 3 is appropriate.

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 precise verb and resource: 'Starts a new agent mesh with THIS machine as its first member.' It explicitly differentiates itself from agent_mesh_join, so an agent can distinguish it from the closest sibling without inspecting other schemas.

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?

Gives explicit usage context: use once on the user's first machine, and every other machine should use agent_mesh_join instead. Also clarifies the idempotent second-call behavior, so no ambiguity remains about repeated invocation.

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