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

With no annotations provided, the description carries the full burden. It adds some behavioral context ('live status') and the verb 'List' implies a read-only operation. However, it does not explicitly state safety, permissions, or potential side effects, though this is a simple list so the risk is low.

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 a single, tightly worded sentence that directly states the action and result. It front-loads the verb 'List' and includes no filler or redundant 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?

For a zero-parameter list tool with no output schema, the description adequately conveys the return content (live status, server counts). It could be slightly more explicit about the exact return structure, but given the simplicity, it is largely complete.

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 input schema is empty, and the description states 'all registries', explicitly clarifying that no filtering or parameters are involved. This adds meaning beyond the schema by indicating the full scope of the operation, exceeding the baseline for zero parameters.

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 uses a specific verb ('List') with a clear resource ('all registries being searched') and defines the output contents ('live status and total server counts'), distinguishing it from sibling tools like search or inspect which operate on content within registries.

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 when one needs to enumerate registries, but provides no explicit guidance on when to choose this tool over alternatives like search or inspect. There is no mention of when not to use it or what other tools are better suited for different scenarios.

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

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It fails to mention that executing payments may be irreversible, incur costs, or require authentication. It also does not explain what 'fund', 'execute', or 'check' actions concretely do. The description only lists supported protocols, leaving significant risk factors undisclosed.

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 two sentences long, front-loads the core purpose, and provides relevant protocol details without fluff. Every sentence contributes meaning, and it is appropriately compact for a tool with a clear function.

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 tool has five parameters including a nested object, no output schema, and no annotations. The description does not explain return values, differences between action modes, or important operational caveats such as idempotency or failure behavior. For a payment tool, this is a significant gap given the lack of structured output information.

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 100%, so the schema already documents all five parameters. The description adds no additional meaning beyond the schema. It does mention 'payment execution' which loosely correlates with the 'execute' action, but this is not a semantic addition to the parameters themselves.

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's purpose: 'Detect payment protocol for any MCP server and route to the correct payment execution.' It names specific supported protocols (x402, MPP, prepaid API keys), which distinguishes it from sibling tools like catalog, inspect, and search. The verb+resource structure is specific and unambiguous.

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 context: it is for payment-related operations on MCP servers. However, it does not explicitly state when to use this tool versus alternatives, nor does it mention any exclusions or when not to use it. The purpose makes it inferable, but there is no direct guidance on selecting this tool over siblings.

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

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the tool returns full metadata and includes payment protocol detection, which conveys a read-only operation. However, it does not disclose potential side effects, error conditions, or whether network access is required, leaving some ambiguity.

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 three short sentences, each earning its place: it states the core function, acceptable inputs, and a notable feature. There is no redundancy or unnecessary detail.

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 tool has a single parameter and no output schema, so the description must infer return value expectations. It explains the full metadata promise and highlights payment protocol detection, giving a reasonable picture of the output. It does not exhaustively list fields, but for a simple inspection tool, it is sufficient.

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 coverage is 100% with the parameter 'identifier' clearly described as a reverse-DNS name, URL, or keyword. The description repeats this exact information but adds no new semantics beyond the schema, so the baseline 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 the tool retrieves full metadata for any MCP server, using a specific verb ('Get') and resource ('MCP server'). It also highlights flexible input formats and a unique feature (payment protocol detection), which helps distinguish it from sibling tools like catalog, checkout, and search.

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 when metadata about a server is needed, and the input flexibility (reverse-DNS, URL, keyword) provides some practical guidance. However, it does not explicitly state when to use this tool over siblings or when not to use it, so it lacks strong usage differentiation.

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

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

With no annotations, the description carries full responsibility. It discloses ranking order (title first, then tool name, then description) and that results include the server's tool list. It does not cover rate limits, empty results, or pagination, but these are not critical for a search tool.

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 and well-structured, with a clear first paragraph and a practical bulleted list for limit settings. Every sentence adds value, no redundancy.

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 search tool with 4 parameters and no output schema, the description covers purpose, ranking, result contents, and limit selection. It does not elaborate on `sources` or `payment_protocol`, but the schema already documents those, so the description is sufficiently complete.

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 coverage is 100%, and the description adds meaningful value beyond the schema by explaining query types with examples and providing specific limit guidelines for different use cases. This exceeds the baseline 3.

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 'Search MCP servers by server title/name, description, or by the tools they provide,' using a specific verb and resource. It differentiates from siblings like catalog/inspect by focusing on discovery through queries, including natural language capabilities.

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?

Provides explicit, actionable guidance on setting the `limit` parameter based on request type (exploratory, task, directive). However, it does not mention when to use search over sibling tools, nor any exclusion criteria.

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