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

With no annotations, the description carries full burden and excels: it discloses that the payload is never sent (only SHA-256), requires a valid agent-guild/caller-proof/v1, and explicitly lists attestation boundaries (integrity, sender auth, issue time—not payload truth, recipient acceptance, or settlement). This is rich behavioral disclosure.

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. The description is front-loaded with 'PAID' and purpose, followed by concise behavioral rules, limits, kinds, and an alternative. No fluff or repetition.

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?

The description covers the core context: purpose, payment, security model, attestation limits, and alternative tool. An output schema exists, so return values don't need explanation. However, parameter semantics are incomplete, and prerequisites for obtaining/using the caller-proof are not detailed, leaving some gaps for a paid tool with this complexity.

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 description coverage is 0%, so the description must compensate. It clarifies payload_sha256 (hash of payload), recipient, and kind (via listed kinds), but leaves many parameters unexplained: nonce, value, reply_to, resource, ttl_seconds, message_context, constraints_sha256, payload_media_type, and api_key. With 12 parameters, this is insufficient for correct invocation.

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 opens with 'Seal one exact machine message or economic intent,' providing a specific verb and resource. It clearly differentiates from sibling tools by explicitly directing users to guild_envelope_verify for free checks.

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?

States the tool is 'PAID' and gives an explicit alternative: 'Use guild_envelope_verify for free checks.' Also provides usage context by listing allowed kinds and explaining the requirement for a caller-proof, giving clear 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.