query_prometheus

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

With no annotations, the description carries the full burden of behavioral disclosure. It does state that results are returned as a table, which is useful, but it does not mention auth requirements, timeout behavior, error handling, or how the cluster parameter affects execution.

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?

A single, front-loaded sentence that contains no filler, tautology, or repetition. It efficiently communicates the action, backend, query type, and result format.

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?

The core action and output format are covered, and an output schema exists to document return values. However, the description omits useful context around the cluster parameter and does not guide the agent toward the range-query sibling for time-series needs.

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 0%, so the description must compensate for the two parameters. 'expr' is reasonably inferred as the PromQL expression, but the 'cluster' parameter is completely unexplained, including its default behavior when empty.

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 uses a specific verb ('Execute') and names a precise resource ('PromQL instant query against Thanos Querier') plus the output form ('table'). The word 'instant' clearly differentiates it from the sibling tool query_prometheus_range.

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 'instant query' wording implies this is for point-in-time metric queries rather than range queries, but the description does not explicitly name query_prometheus_range or state when one should be chosen over the other. Usage guidance is implied rather than explicit.

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