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

Annotations already declare readOnly=false, destructive=true, and idempotent=false, so the mutation profile is known. The description goes further by disclosing the CA-minting lifecycle, peer-list re-render, Cilium reconfiguration, and multi-minute convergence, plus refusal semantics with reasons. However, it omits auth/permission requirements and rollback/reversibility of the reconfiguration, so it is strong but not exhaustive; a 3 relative to annotation-covered safety baseline.

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 core action, then effects, then preconditions. Four sentences, none wasted, with the readiness prerequisite given prominent placement.

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 two-parameter mutation tool with no output schema, the description covers lifecycle effects, timing, refusal behavior, and prerequisites, leaving nothing an agent needs 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?

Schema description coverage is 100%, so mesh_id and cluster_id are fully documented in the schema. The description adds no format, syntax, or ID-source detail beyond that, which is the expected baseline when the schema carries the load.

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+resource ('Add one cluster to a mesh') and immediately distinguishes it from sibling operations by describing the CA-minting and peer-list re-render effects. An agent can tell this apart from create_cluster_mesh, remove_cluster_from_mesh, and check_cluster_mesh_readiness without opening any 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 sequencing and preconditions: run check_cluster_mesh_readiness first before attempting a join, and remove the cluster from any existing mesh before joining. This is actionable when-to-use and when-not-to-use guidance with named alternatives.

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