espn_core_call

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

Annotations already indicate read-only, idempotent, and open-world behavior. The description adds valuable context beyond annotations: auth requirements ('none needed'), the $ref-linked envelope and the need to follow refs for detail, and a caution about the plural 'leagues' path. No contradictions with 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 a single paragraph but well-structured, front-loading the purpose and scope. The enumerated content categories are dense but relevant, and the Note/Returns/Auth lines are clear. Slightly long, but no wasted sentences.

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 output schema, the description compensates by explaining the response envelope ($ref, count, items) and how to access detail. It covers operation discovery, required inputs, and auth. It lacks pagination and rate-limit details, but for an open-world gateway with annotations, this is reasonably complete.

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 covers all three parameters with descriptions, but the tool description adds meaningful examples for path_params (sport, league, eventId/competitionId/athleteId/year) and explains the operation concept. It also directs users to the operations resource for valid operation names, which complements the schema's pointer to list_resources.

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 identifies the tool as a gateway to the ESPN core data model, lists specific content areas (athletes, statistics, odds, plays, etc.), and notes the path uses 'leagues/{league}'. It distinguishes itself from other ESPN tools by naming the core API surface and instructing users to browse the espn://core/operations resource.

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 practical guidance on how to use the tool (supply operation + path_params, follow $ref links, browse operations). It implies this is the canonical/deepest surface, but does not explicitly state when to choose this over sibling ESPN tools like espn_site_call or espn_web_call, nor when not to use it.

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