MCP Registry Server

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. However, the description adds little beyond restating the purpose. It says 'all registered' but does not clarify that filters can narrow results, potentially misleading the agent about the default scope. No pagination or ordering behavior is disclosed.

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 redundant: 'List MCP servers' and 'Returns a list of all registered MCP servers' convey the same information. The dash-separated structure wastes space without adding value. It is short but not well-structured.

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 list tool with five optional parameters and no output schema, the description is incomplete. It does not mention pagination (cursor, limit), search, version filtering, or updated_since semantics, nor any return format details. Annotations cover the read-only aspect, but the overall usage context is insufficient.

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 schema description coverage is 0% for five parameters, and the description provides no explanations for limit, cursor, search, version, or updated_since. The agent has no semantic understanding of these filter/pagination parameters from the description.

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 action ('List') and resource ('MCP servers'), and explicitly says it returns 'a list of all registered MCP servers'. While it doesn't directly differentiate from sibling tools (which focus on server versions), the name and phrasing make the purpose clear.

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 guidance is provided on when to use this tool versus the sibling tools, nor are the optional parameters (limit, cursor, search, version, updated_since) explained. There is no mention of filtering, pagination, or when to use a more specific version-related tool.

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?

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds useful behavioral context beyond annotations: it specifies the result is ordered by publication date (newest first) and that it returns 'all available versions'. This provides additional expectation-setting without contradicting annotations.

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, using two short phrases separated by a dash, with the key action front-loaded. Every word adds value: it names the resource, specifies the scope ('all versions', 'specific MCP server'), and adds the ordering detail. No filler or 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?

Given the tool's simplicity (one parameter, no output schema, read-only annotations), the description is mostly complete. It clearly states what the tool returns. Minor gaps like pagination or response format are not mentioned, but for a simple listing tool with good annotations, this is acceptable. It is not overburdened and covers the essential context.

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 has only one parameter (serverName) with 0% description coverage. The description says 'for a specific MCP server', which gives vague meaning but does not explain what serverName is, how to obtain it, or any format requirements. With no schema description, the description should compensate but minimally does, leaving the parameter semantics unclear.

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: 'List all versions of an MCP server' and elaborates with 'Returns all available versions for a specific MCP server, ordered by publication date (newest first)'. The verb 'List' and the resource 'versions of an MCP server' are specific, and it distinguishes from sibling tools like getV01ServersServerNameVersionsVersion (likely a single version) by emphasizing 'all versions'.

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 when to use the tool: when you need all versions of a server. However, it does not explicitly mention alternatives or provide when-not-to-use guidance. There is no reference to sibling tools or exclusions, so usage guidelines are only implied, not stated directly.

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?

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds useful behavioral context about the 'latest' special version and promises detailed information, going beyond the structured annotations without contradicting them.

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-loaded with the primary action and purpose, and contains no redundant or filler content.

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 simple read-only tool with two string parameters, the description adequately covers purpose and key behavior. The lack of an output schema is somewhat mitigated by the straightforward nature of the tool; more detail on return structure would be nice but is not essential.

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 explains the 'version' parameter's special value ('latest') and clarifies the resource context. The 'serverName' parameter is self-explanatory from the tool name and context, making the description sufficient for both 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 ('Get') and clearly identifies the resource ('specific MCP server version'), distinguishing it from sibling tools that list servers or versions. The mention of the special 'latest' value adds further precision.

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 clearly implies when to use the tool (retrieve a specific version) and provides guidance on using the 'latest' special value. It does not explicitly name alternatives, but the sibling tool names make the distinction self-evident.

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