List PostgreSQL clusters

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds meaningful behavior beyond that: results are filtered by namespace/cluster allowlists and protected clusters are flagged. This is useful disclosure of filtering behavior and result semantics.

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 short sentences, each earning its place: the first defines the resource, the second gives the key namespace usage tip, and the third discloses filtering/flagging behavior. No fluff, well 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 simple read-only list operation with two optional parameters fully documented and comprehensive annotations, the description is nearly complete. It covers scope, namespace behavior, and result filtering; only minor details like output shape or pagination are absent, but with no output schema these are not critical for correct invocation.

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% for both parameters, so the baseline is 3. The description adds extra meaning for the namespace parameter by explaining that omitting it lists across all namespaces, which is not stated in the schema. This lifts it above the baseline.

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 names a specific verb ('List'), a specific resource type ('PerconaPGCluster resources'), and clarifies the scope ('PostgreSQL + PgBouncer'). This clearly distinguishes it from siblings like get_cluster, get_cluster_status, list_backups, and list_restores.

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 gives clear context for use: listing PerconaPGCluster resources, with explicit guidance on omitting namespace to list across all namespaces. It does not explicitly name alternatives or when-not-to-use, so it stops short of a 5.

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