mcp-rubber-duck

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. The description mentions it's for 'evaluate and rank' and should be used 'after duck_council,' but doesn't disclose critical behavioral traits: what the output looks like (ranking format, scores), whether it's a read-only or mutating operation, authentication needs, rate limits, or error conditions. For a tool with no annotation coverage, this is a significant gap.

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 appropriately sized and front-loaded: two concise sentences that immediately convey the core purpose and usage context. Every sentence earns its place with no wasted words or redundant information.

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 complexity (evaluation/ranking tool with 4 parameters), no annotations, and no output schema, the description is incomplete. It doesn't explain what the tool returns (ranking format, scores, or structured output), behavioral constraints, or error handling. For a tool that performs comparative evaluation with multiple inputs, this leaves significant gaps for an AI agent.

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%, so the schema already documents all four parameters thoroughly. The description adds minimal value beyond the schema: it implies 'responses' come from 'duck_council output' and mentions 'evaluate and rank,' but doesn't provide additional syntax, format details, or usage examples. Baseline 3 is appropriate when the schema does the heavy lifting.

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: 'Have one duck evaluate and rank other ducks' responses.' It specifies the verb ('evaluate and rank'), resource ('other ducks' responses'), and distinguishes it from siblings by mentioning duck_council as the source. However, it doesn't explicitly differentiate from compare_ducks or duck_vote, which might have overlapping functionality.

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 clear context for when to use this tool: 'Use after duck_council to get a comparative evaluation.' This gives a specific prerequisite and timing. However, it doesn't explicitly state when not to use it or mention alternatives like compare_ducks or duck_vote, which could be relevant for ranking/evaluation tasks.

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