Disco

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

The annotations provide readOnlyHint=true, indicating a safe read operation. The description adds valuable context beyond this by detailing what the response includes (patterns, feature importance, summary, etc.) and the dashboard_urls object with links to interactive reports. It doesn't contradict annotations and enriches understanding of the tool's behavior and output structure.

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 well-structured and front-loaded, starting with the core purpose, then detailing the response, usage guideline, and parameters. Every sentence adds value without redundancy, making it efficient and easy for an agent to parse quickly.

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 (fetching results of a data analysis run), the description is complete: it explains the purpose, output content, usage timing, and parameters. With annotations covering safety and an output schema presumably detailing the return structure, no critical gaps remain for effective agent use.

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 0% schema description coverage, the description compensates by explaining both parameters: run_id ('The run ID returned by discovery_analyze') and api_key ('Optional if DISCOVERY_API_KEY env var is set'). It adds meaning beyond the bare schema, clarifying sources and optionality, though it could provide more detail on format or constraints.

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 ('Fetch the full results') and resource ('a completed Disco run'), distinguishing it from siblings like discovery_status (which checks status) or discovery_analyze (which initiates analysis). It precisely defines what the tool does without being vague or tautological.

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 states when to use this tool: 'Only call this after discovery_status returns "completed".' It provides a clear prerequisite and distinguishes it from alternatives by specifying the required state of the Disco run, guiding the agent on proper sequencing.

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