ReftrixMCP

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

Beyond the readOnly/idempotent annotations, the description adds valuable behavioral context: it clarifies the comparison is 'parallel,' specifies that it 'reports property-level identity' (indicating granular diff-style output), and enumerates the four comparable aspects. This helps agents understand the depth of analysis performed.

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 tightly structured with zero redundancy—each clause conveys distinct information (scope, aspects, default, output type). The bilingual format efficiently serves international contexts without duplication of meaning, and the information is front-loaded with the core action.

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 2-parameter comparison tool with complete schema coverage and safety annotations, the description adequately covers the essential behavioral traits and hints at output characteristics ('property-level identity'). It would benefit from explicit mention of return value structure, but given the annotations cover safety and the schema covers inputs, the description provides sufficient context for invocation.

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?

With 100% schema description coverage, the schema fully documents both parameters (part_ids constraints and compare_aspects enum/default). The description reinforces the 2-5 range and default aspects but adds no additional syntax, format details, or semantic nuances beyond what the schema already provides, meeting the baseline for high-coverage schemas.

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 explicitly states the tool performs parallel comparison of 2-5 UI parts across four specific dimensions (styles, layout, interaction, accessibility), clearly distinguishing it from siblings like design.compare (which handles designs) and part.inspect (which analyzes single parts). The bilingual text maintains specificity in both languages.

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 effectively communicates default behavior (styles+layout) and the specific comparison scope, helping agents understand what happens when compare_aspects is omitted. However, it lacks explicit guidance on when to prefer this over design.compare or part.inspect, though the 'UI parts' specificity provides implicit differentiation.

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