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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds context about the return payload (freshness timestamp, promotion label), which is useful. It doesn't mention side effects or permissions, but given the strong annotation coverage, this is adequate.

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?

The description is redundant: it repeats the return values ('Returns: ...') after already mentioning them earlier. The example 'call federation_choice_get with arguments {}.' is misleading because tenant_id is required but omitted. This prevents the description from being concise or well-structured.

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 simple read tool with one parameter and no output schema, the description adequately covers what it returns (choice_profile envelope, freshness, promotion label) and when to use it. It's complete for typical invocation, though the misleading example slightly detracts.

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?

The schema provides 100% coverage for the single parameter tenant_id with a clear description ('The tenant whose profile to fetch'). The description adds no extra meaning beyond what the schema already establishes, 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?

The description clearly states the tool fetches a tenant's full choice_profile, freshness, and promotion label. It uses a specific verb ('fetch') and explicit resource ('tenant's choice_profile'), and distinguishes itself by referencing federation_choice_compare as a prior step, which sets it apart from siblings like federation_canon_get.

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 description gives explicit guidance: 'Use after federation_choice_compare has narrowed to a single tenant.' This tells the agent when to invoke it and implies it's not for initial selection. It doesn't explicitly name alternatives, but the reference to a specific prior tool provides clear context.

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