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

Annotations only declare readOnlyHint=true; the description goes well beyond that by defining the eligible/ready/ineligible semantics and explaining per-check remediability, including which cloud/distribution/CNI attributes cannot be changed on a running cluster. This is exactly the behavioral context an agent needs and cannot get from the annotation or schema.

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?

Front-loaded with the purpose, then the eligible/ready distinction and remediation routing. Dense and largely waste-free, though the remediable/cloud/CNI clause is long enough to be slightly heavy for a single paragraph.

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?

There is no output schema, so the description must carry return-value meaning, and it does by defining eligible, ready, and remediable. Combined with the read-only annotation and the prerequisite relationship to create_cluster_mesh, an agent has everything needed to call 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?

Schema coverage is 100% and the single parameter is already documented as 'Cluster UUIDs to judge as one candidate mesh', so the baseline is limited upside. The description still adds value by clarifying 'Takes CLUSTER ids, not a mesh id', which prevents a plausible misuse.

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+resource: judging whether given clusters could form one mesh, with failing checks reported per cluster. It explicitly distinguishes itself from create_cluster_mesh and make_cluster_mesh_ready, so an agent can route correctly without opening a schema.

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 when-to-use and alternatives: 'Always run this before create_cluster_mesh', and route to make_cluster_mesh_ready when a failing check is remediable. It also names the alternative outcome (rebuild for ineligible clusters), leaving nothing to inference.

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