opendota_leagues

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

Beyond the readOnlyHint/idempotentHint/openWorldHint annotations, the description adds valuable behavioral context: the response is LARGE (~1 MB), includes historical events, returns a specific structure, and requires no authentication. This enriches the agent's understanding of response size and field formats without contradicting annotations.

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 concise and front-loaded with the core purpose. It packs essential details (size, return fields, example, auth) into a few well-organized lines without any redundancy. Every sentence adds value.

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 simple, no-parameter read-only list tool, the description is complete: it covers the data scope, size warning, return schema, example usage, and authentication. There is no output schema to rely on, so these details are essential and provided clearly.

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?

The tool has zero parameters, and the schema coverage is vacuously 100%. The description compensates by explaining that filtering is done client-side (since no server-side filter parameters exist), which clarifies why there are no inputs. This goes beyond the baseline expectation for a no-parameter tool.

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 states exactly what the tool does: it returns every Dota 2 league/tournament known to OpenDota. The verb 'Returns' and specific resource ('league/tournament') are clear, and it distinguishes itself from sibling OpenDota tools by covering the complete set of leagues.

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 gives clear context for when to use the tool (when you need all leagues/tournaments) and even advises to filter client-side by tier. It does not explicitly name alternatives or exclusions, so it doesn't reach a 5, but the guidance is solid for a simple list tool.

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