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

Goes well beyond the readOnly/idempotent annotations by disclosing data provenance ('answers come from Stackduke's published tracker data'), that no vendor server is contacted, and the ~daily refresh cadence. These are exactly the operational facts an agent needs to reason about staleness and side effects.

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-loads what is listed, then the returned fields, then freshness, then the read-only guarantee — a logical order with no filler. The parenthetical kind list is dense but genuinely informative rather than redundant.

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?

With an output schema present, the description needn't specify return values, yet it still summarizes the per-server fields (tool count, kind breakdown, last checked, last listed), and it covers scope, freshness, and safety. Nothing an agent needs to invoke it correctly is missing.

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 tool takes zero parameters, so the baseline is 4; there is nothing parameter-wise for the description to compensate for. Schema coverage is 100% and no enum or nested semantics exist.

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 and resource ('Lists the official vendor MCP servers that Stackduke's public tracker follows') and immediately scopes it with 'Only these servers are covered,' so an agent can tell this apart from a per-server lookup like get_server_capabilities. It stops short of naming the sibling tools outright, which keeps it from a top score.

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 clear context for use: this is the enumeration of tracked servers, and the data refreshes 'about once a day,' which tells the agent how much to trust freshness. There are no explicit when-not-to-use statements or named alternatives, so it falls short of a 5.

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