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

Annotations already declare readOnlyHint and idempotentHint, and the description's trailing 'Read-only' merely restates them (no added credit, but no contradiction). The real value added is the disclosure of what the call returns – usage broken down by project and metric alongside limits – which matters because there is no output schema.

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?

Front-loaded with the purpose and metrics in a single efficient sentence. The trailing 'Read-only' sentence is pure redundancy with the annotations and could be dropped.

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 parameters, no output schema and full annotation coverage, the description supplies the missing piece – which metrics come back, per project, against plan limits. It stops short of format/granularity details but is sufficient to call the tool correctly.

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?

Zero parameters, so there is nothing to document; the description correctly omits parameter talk rather than inventing it. Baseline of 4 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?

States a specific verb+resource (shows Search usage vs plan limits) and scopes it with the exact metrics covered: projects, items indexed, searches, per project. This clearly separates it from siblings like search_list_projects, though it doesn't name an alternative explicitly.

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?

Usage is only implied by mention of 'plan limits' – an agent can infer it is the quota/quota-check tool, but there is no explicit when-to-use, when-not-to-use, or pointer to a sibling for related questions (e.g., listing projects).

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