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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds meaningful behavioral context: parallel execution, the ability to pass 'all' for active tenants, the public-read nature making auth_token optional, the exact return shape, and an example call. This adds value beyond the boolean hints without any contradiction.

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?

Every sentence earns its place: purpose, behavior, alternatives, parameter origin, auth note, return shape, and example — all in three dense sentences. Well front-loaded with the core action, no fluff.

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 multi-tenant search tool with two required and three optional parameters, the description covers parallel execution, tenant enumeration, authentication nuance, output format, and example invocation. Even without an output schema, the return shape is fully documented. This is as complete as one could expect.

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%, so baseline 3 applies. The description goes further by explaining tenant_ids accepts 'all', clarifies the semantic of flat results (one row per variant), and includes a full invocation example. Minor deduction because more detail on limit/category would have been nice, but the description clearly supplements 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?

The description states 'Search products (flat — one row per variant) across multiple tenants in parallel' — a specific verb, resource, and scope. It explicitly distinguishes from the sibling tool by calling out 'flat' and by cross-referencing the grouped variant, making it clear what makes this tool unique.

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?

Explicitly instructs when to use the alternative: 'Use federation_catalog_search_grouped_multi for browse/discovery flows to get token-efficient family rollups.' It also tells where tenant_ids comes from (federation_list_tenants) and notes auth is optional, covering both tool selection and prerequisites.

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