mcp_explain_tool

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

readOnlyHint=true already tells the agent this is a safe non-mutating operation, lowering the disclosure bar. The description adds the useful detail that the output covers adapter, protocol, local operation, and input schema, but says nothing about error behavior when the name is unknown or the tool is unregistered.

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?

A single front-loaded fragment that wastes no words. It is terse to the point of being a colon-list rather than a sentence, but every token carries 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?

There is no output schema, so the description doing double duty by enumerating the explained facets is valuable. For a single-read-only-parameter introspection tool this is nearly sufficient; a note on failure mode for unknown names is the only notable gap.

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% and the schema already provides a format example ('openapi.widgets.getWidget'). The description contributes nothing beyond what the schema states, so the baseline 3 applies.

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 (Explain) and a specific resource (a namespaced MCP tool), and enumerates the facets returned: adapter, protocol, local operation, input schema. This distinguishes it from enumerating siblings like mcp_list, though it never names an alternative explicitly.

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 when-to-use guidance, no prerequisites, and no mention of alternatives such as mcp_list or mcp_query_by_protocol. The agent must infer that this is a follow-up to enumeration purely from the tool name and the 'namespaced' qualifier.

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