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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new context: it is a paid x402 tool with a concrete price ID, and it enumerates the returned payload (identifiers, lineage, survivorship, freshness, relationships, quality) — valuable 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?

Three tight sentences, front-loaded with the payment model and the core action, then the return inventory. Nothing repeats the title or wastes a clause.

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 2-param read tool with no output schema, the description successfully compensates by listing the return contents and disclosing the paid/x402 pricing. Minor gaps remain: not-found behavior, cost magnitude, and whether payment is per-call.

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?

With 50% schema description coverage, the schema already documents record_id and the entity_type enum. The description only echoes 'stable record ID' and adds no format, expected ID shape, or domain-specific caveat for either parameter, so it barely improves on the structured fields.

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 – retrieve one authoritative public golden record by stable record ID – and enumerates what is returned, so the agent knows exactly what it gets. It never names a sibling (search_master_data, resolve_master_data_entity) to contrast against, so differentiation is left to inference.

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?

No explicit when-to-use, when-not-to-use, or alternative routing appears in the description; the only sibling routing hint ('reference data is served by get_reference_data') lives in the schema's enum text, not here. An agent must guess whether to call this or search_master_data/resolve_master_data_entity when it only has an approximate identifier.

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