unphurl-mcp

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

With no annotations provided, the description carries the full burden and does well: it discloses pagination behavior, default/maximum results, retention period (90 days), and account-level stats permanence. It doesn't cover error cases or authentication needs, but adds substantial behavioral context beyond basic purpose.

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 front-loaded with the core purpose, followed by pagination details and retention info. Every sentence adds value: the first defines the tool, the second explains navigation, and the third clarifies data lifespan. No wasted words, and structure is logical.

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 no annotations and no output schema, the description is quite complete for a read-only list tool: it covers purpose, usage, pagination, limits, and data retention. It could mention response format or error handling, but for complexity level, it provides sufficient context for an agent to use it 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?

Schema description coverage is 100%, so the schema already documents page and limit parameters fully. The description mentions pagination and default/max values, which aligns with but doesn't add significant meaning beyond the schema. Baseline 3 is appropriate as 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 specific action ('View recent URL check history') and resource ('URL check history'), distinguishing it from siblings like check_url (single check) or get_stats (account stats). It specifies what data is shown: URLs checked, scores, phishing status, and credit usage, making the purpose explicit and differentiated.

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: to view historical checks with pagination and retention details. It doesn't explicitly state when not to use it or name alternatives, but it implies usage for historical data versus real-time checks (like check_url). No misleading guidance is present.

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