metrics_get_resource_usage_metrics_by_project

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is fully covered elsewhere. The description adds only a restatement of the HTTP endpoint, which duplicates the annotation title; it says nothing about aggregation window, time-range constraints, or whether there are no time parameters at all — a real gap for a metrics aggregation tool.

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?

Two short lines, front-loaded with the purpose, no filler prose. The embedded GET path is largely redundant with the annotation title but is at least compact rather than verbose.

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 convey what comes back, yet 'aggregated metrics values' is undefined — no metric names, units, dimension set, or time bucketing. For a metrics aggregation endpoint with two parameters and no return documentation, an agent cannot predict the result shape well enough.

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% (projectId marked '(path)', apiVersion documented with format guidance), so the schema carries the load. The description adds no extra meaning such as whether projectId accepts a UUID or name, so baseline 3 applies.

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?

Specific verb + resource + scope: 'Returns aggregated metrics values of the given project' tells the agent this is an aggregation read scoped to one project, and the embedded path confirms the projectId path parameter. It does not name or contrast with the near-identical siblings metrics_get_resource_usage_metrics and metrics_get_resource_usage_metrics_by_user, so sibling discrimination rests mostly on the tool name.

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?

No statement of when to use this versus metrics_get_resource_usage_metrics (unscoped) or metrics_get_resource_usage_metrics_by_user. It also never says whether the project must exist or what happens if it doesn't. The agent must infer the choice from the name alone.

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