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

The description discloses that it returns a SaSame-signed, offline-verifiable statement, and that unknown IDs return an error (no fabricated empty flags). This adds significant behavioral context beyond the readOnlyHint annotation, covering output format and error handling.

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 concise with two sentences. The first sentence front-loads the core functionality and outputs, and the second adds essential details about verification and error handling. No extraneous information.

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?

Despite lacking an output schema, the description enumerates key return categories (status, risk_flags, display_strength, correction chain, audit trail) and explains the signed nature and error behavior. This is sufficient for an agent to understand what the tool returns and how to handle errors.

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 only parameter receipt_id has schema description 'rcp_* or atr_* id', and the description re-emphasizes this format. With 100% schema coverage and only one param, the description adds little additional semantic value beyond what the schema already provides. Baseline score of 3 is appropriate.

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 it reads the lifecycle state of a receipt, listing specific outputs like status, risk flags, display strength, correction chain, and audit trail. It is specific to the receipt_state tool and distinct from sibling mutation tools like receipt_issue or receipt_status_set.

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 implies usage for querying receipt state and notes behavior for unknown IDs (returns error). However, it does not explicitly differentiate from siblings like receipt_status_set or factory_verify_receipt. The readOnlyHint in annotations helps, but the text itself lacks explicit when-to-use guidance.

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