Server Info

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

Annotations only declare readOnlyHint=true, so the description adds real value by disclosing the conditional nature of one field ("when configured, the upstream service's version") and that the payload is connection-scoped ("the revision and client of this connection"). It stops short of saying the call has no side effects or that results are static from server start, but the safety profile is already covered by 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?

Front-loaded with the verb and purpose, followed by a usage sentence. The middle field list is dense but each named field earns its place by telling the agent what questions this tool can answer; it is slightly encyclopedic for a zero-argument call.

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?

An output schema exists, so return values did not need spelling out, yet the description still signals the key conditional (optional upstream version) an agent would otherwise misread. For a zero-parameter, read-only introspection tool this is fully 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?

There are no parameters, so the baseline is 4; the description correctly says nothing about inputs rather than inventing them. Nothing further can be added on this dimension.

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?

Uses a specific verb and resource ("Report the version information of markdown-vault-mcp") and enumerates exactly what comes back: server_name, server_version, core_version, supported protocol revisions, this connection's revision/client, and optionally the upstream service version. No sibling tool does version introspection, and the description makes that scope unmistakable.

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?

Gives a clear trigger condition: "Use it when asked which version or build is running or which protocol revision is in use." That covers the realistic invocation contexts. It doesn't name an alternative or a when-not case, but with zero sibling overlap there is little to route against.

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