about

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

With annotations already declaring readOnlyHint=true and destructiveHint=false, the description adds useful context by enumerating the returned data elements (server identity, version, data sources, runtime capabilities). However, it does not disclose additional behavioral traits such as response format, caching, or authentication requirements. The bar is lower due to annotations, but this is only a modest improvement over the annotation's safety profile.

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, well-structured, and front-loaded with the main outcome. The first sentence states what the tool returns; the second adds a usage scenario and an alternative. Every sentence earns its place, with zero fluff or repetition of schema fields.

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 tool with no parameters, no output schema, and simple read-only behavior, the description is complete. It explains the return content, the use case, and even an alternative access method. No further context is needed to understand when and how to use this tool effectively.

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 has zero parameters, so schema coverage is 100% and there are no parameter semantics to clarify. The baseline for 0 parameters is 4, and the description does not need to explain anything about parameters since there are none. It correctly implies no arguments are needed by omitting any mention of them.

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: 'Return server identity, version, data sources, and runtime capabilities.' It uses a specific verb ('Return') and resource (server metadata), making it distinct from sibling tools that search or fetch specific legal data. It also explains the use case of discovering tier and capabilities, which further clarifies its unique role.

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 explicitly says 'Use this tool to discover what tier and capabilities are available' and provides an alternative: 'Equivalent to reading the MCP resource case-law-stats://dutch-law-mcp/metadata but callable as a tool.' This gives clear context on when to use the tool and even names the resource alternative, satisfying the 'alternatives' criterion.

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