mcp-server-devutils

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states the basic action ('test a regular expression against a string') without detailing traits like error handling, output format, performance implications, or rate limits. This is inadequate for a tool with no annotation coverage, leaving significant gaps in understanding its behavior.

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 a single, clear sentence: 'Test a regular expression against a string.' It is front-loaded, efficient, and wastes no words, making it easy to understand quickly. Every part of the sentence contributes directly to the tool's purpose.

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 complexity (regex testing with parameters) and the lack of annotations and output schema, the description is incomplete. It does not explain what the test returns (e.g., matches, groups, boolean result), error cases, or behavioral details. For a tool with no structured output or annotations, more context is needed to be fully helpful.

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%, with all parameters (pattern, flags, testString) well-documented in the schema. The description does not add any meaning beyond what the schema provides, such as examples or usage notes. According to the rules, with high schema coverage, the baseline is 3 even without param info in 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 tool's purpose: 'Test a regular expression against a string.' It specifies the verb ('test') and the resource ('regular expression'), making the function unambiguous. However, it does not differentiate from sibling tools, which are unrelated (e.g., base64_encode, json_format), so it lacks explicit sibling distinction.

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 provides no guidance on when to use this tool versus alternatives. It does not mention any context, prerequisites, or exclusions, and there is no reference to sibling tools or other methods for regex testing. Usage is implied by the name and description alone, with no explicit instructions.

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