list_projects_metrics

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely non-obvious behavior: identifiers are resolved before the request and an unknown or ambiguous name aborts the entire call, listing candidates. That all-or-nothing failure mode is valuable context, though auth/rate-limit behavior is not addressed.

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?

Four compact sentences, front-loaded with what is read, then usage, then safety, then failure behavior. The parenthetical enumerating the counters is dense but informative, and no sentence is filler.

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 an output schema present, the description need not detail return values, and the annotations carry the read-only profile. It covers the remaining agent-critical unknowns: batch semantics, sibling routing, and identifier-resolution failure handling.

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 coverage is 100% and the single 'projects' parameter already documents 'by name, code or id', so the description's restatement earns no credit. It does, however, add resolution semantics for the parameter values — that an unresolvable name fails the whole call and returns candidates — which goes beyond the schema.

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 specific verb and resource ('Read budget and time counters'), enumerates exactly what is returned (budget amount, budget spent, planned and elapsed time), and scopes it to 'several projects in one call'. It explicitly distinguishes itself from the sibling get_project_metrics, so an agent can route without opening either 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 both a positive use case ('compare projects or build a portfolio view') and the named alternative with the condition that selects it ('use get_project_metrics for a single project'). Nothing about when to pick this over its sibling is left to inference.

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