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

Beyond the readOnlyHint annotation, the description discloses meaningful behavior: what 'pending', 'stale', 'scheduler_down', 'agent_outdated', 'snapshot_rejected', 'snapshot_stale' and 'nodes_unavailable' each mean, and specifically which states result in 'nothing is offered'. That is substantial operational context an agent cannot get from the annotation alone.

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?

It is front-loaded with the returned fields and the status semantics are genuinely useful, but the content is delivered as a single dense run-on sentence with a very long nested parenthetical, which hurts scanability. It earns most of its length but could be broken into structure.

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?

With no output schema, the description usefully compensates by enumerating return fields and status meanings, and it notes cluster creation via POST /api/clusters. For a zero-parameter read tool this is quite complete; only a plain statement that this is a listing call 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?

The tool takes zero parameters, so the baseline is 4. The only parameter-like reference (target {cluster_id}) belongs to mcg_quote, not this tool, so there is no parameter semantics to add.

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 establishes the resource (connected clusters) and enumerates the fields returned (id, name, preset, status, classes, etc.), making the tool's purpose evident as a cluster listing/inspection call. It does not state the verb explicitly and differentiates only loosely from siblings like mcg_catalog, but the resource scope is unmistakable.

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?

It provides one concrete downstream linkage – 'Pass target {cluster_id} to mcg_quote to run there at zero hardware cost; only a connected cluster quotes' – which implies when this tool matters. However, it never states when to call this versus other list/inspection siblings, and offers no explicit exclusions, so guidance is implied rather than spelled out.

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