Server Quality Checklist

Tool Scores

• x402_healthB
  3.3/5.0
  Behavior3/5

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

  Annotations already declare readOnly and idempotent hints. The description adds 'real-time' and 'no payment required,' which are minor behavioral clarifications. It does not disclose any additional traits like rate limits or result details.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is only two sentences, each adding distinct value: the first states the primary function, the second clarifies cost. No unnecessary words or repetition.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness2/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Despite the presence of an output schema, the description does not mention the parameter or what the health status response contains. For a tool with one required parameter and no schema description, the description should provide more context to be complete.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters1/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  The input schema has 0% description coverage for the single parameter 'service_id,' and the description does not explain its meaning or format. The parameter's purpose is left entirely to inference from the tool name.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose5/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the tool checks real-time health status of x402 services, which is a specific verb and resource. It distinguishes from sibling tools like x402_register or x402_browse which have different purposes.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines3/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description mentions 'Free, no payment required,' hinting that other tools may incur costs, but it does not explicitly state when to use this tool versus alternatives or provide exclusions. The purpose is implicit but not directive.

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

• x402_attestA
  3.7/5.0
  Behavior4/5

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

  Annotations already provide readOnlyHint=true and destructiveHint=false. Description adds valuable context: the attestation is a JWT with specific fields (uptime, latency, health, compatibility) and references offline verification via JWKS. No contradictions with annotations.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness4/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  Three sentences packing essential info (purpose, content, verification, spec reference). Front-loaded with verb 'Fetch' and noun. Could be slightly improved by mentioning the raw parameter briefly.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given annotations and output schema exist, description covers verification and content but omits explanation of the raw parameter and prerequisites for service_id. Incomplete for a tool with 0% schema description coverage.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters2/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 0%, yet the description does not clarify the semantics of the two parameters (service_id and raw). It fails to add meaning beyond the schema's basic type and required status.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose5/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  Description clearly states the tool fetches a signed discovery attestation (EdDSA JWT) for a registered x402 service. It specifics the content (quality measurements) and verification method, distinguishing it from sibling tools like x402_browse or x402_register.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines3/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description implies usage for obtaining attestations for registered services but does not explicitly state when to use vs alternatives, nor does it provide conditions or exclusions.

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

• x402_discoverA
  3.9/5.0
  Behavior4/5

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

  Annotations already indicate read-only, non-destructive, idempotent, and open-world behavior. The description adds transparency by disclosing the $0.010 USDC cost per query, which is a behavioral trait not captured in annotations.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  Two sentences, each adding value, with front-loaded purpose and key details. No wasted words.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness4/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Description covers return content (quality-ranked results, uptime%, latency, pricing, code snippets) and cost. With annotations and output schema likely providing further detail, it is mostly complete, though error handling and pagination are not mentioned.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters2/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema coverage is 0% with no parameter descriptions. The description mentions 'capability or keyword' hinting at query and capability params, but fails to explain max_price_usd and min_quality. Insufficient detail for a 4-parameter tool.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose5/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the tool finds x402-payable services by capability or keyword, specifying the resource and action. It distinguishes itself from sibling tools with different purposes like attest, browse, health, and register.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines3/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description implies usage for discovering services but does not explicitly state when to use this tool over alternatives or provide exclusions. No guidance on prerequisites or when not to use it.

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

• x402_registerA
  4/5.0
  Behavior4/5

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

  Annotations already indicate readOnlyHint=false and openWorldHint=true, which align with the 'Register' action. The description adds useful behavioral context: the service will appear in the catalog and be discoverable, and it is free. No contradictions. It does not detail side effects beyond creation, but the disclosure is adequate for the tool's simplicity.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  Two concise sentences, front-loaded with the action verb 'Register'. No redundant or filler content; every sentence adds distinct value.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  While the outcome (service appears in catalog) is mentioned, the description omits details about the response (though an output schema exists), required prerequisites, or parameter constraints. Given 7 parameters and a creation operation, the description is minimally complete but leaves gaps.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters2/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 0%, and the description provides no information about any of the 7 parameters (name, endpoint_url, etc.). The description entirely fails to add meaning beyond the schema, leaving the agent to infer from parameter names alone.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose5/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states 'Register a new x402 service with the discovery index,' specifying the exact verb and resource. It also distinguishes itself from sibling tools like x402_browse or x402_discover by focusing on registration.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines4/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides context on when to use the tool ('Register a new x402 service') and states that it is free, implying cost is not a concern. However, it does not explicitly mention when not to use it or suggest alternatives, lacking exclusionary guidance.

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

• x402_browseA
  4.7/5.0
  Behavior5/5

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

  Adds 'Free, no payment required' and 'Returns full catalog with quality signals' beyond annotations (readOnly, destructive, idempotent, openWorld). Provides cost model and output characteristics.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  Three sentences: action, cost, output. Efficient and front-loaded with essential information. No wasted words.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness5/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  With one optional parameter and an existing output schema, the description fully covers purpose, cost, and output nature, leaving no significant gaps.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters4/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Single parameter 'category' has no schema description (0% coverage). Description clarifies it as optional filter, adding meaning beyond schema's minimal title.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose5/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  Description clearly states verb 'browse', resource 'registered x402 services', and optional filter by category. Distinguishes from sibling tools like x402_attest, x402_discover, etc.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines4/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  States 'Free, no payment required' as a usage condition. Implicitly context for browsing vs. other operations, but no explicit when-not or alternatives beyond tool names.

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