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

Adds substantial behavior beyond the annotations: bounded execution (one socket, closes after at most 5 seconds, 50 messages or 256 KiB) and no ongoing background delivery, which tells the agent this is a one-shot sample rather than a subscription. Auth/entitlement requirements are also disclosed. The annotations already carry the read-only/idempotent safety profile, so this is strong but not exhaustive (no error/failure-mode detail).

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?

Three dense sentences, zero filler, with the routing constraint and access prerequisites front-loaded ahead of the execution-bound details. Every clause carries information an agent needs.

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?

An output schema exists and the annotations cover safety, so the description's job is mostly routing, auth, and lifetime semantics — all of which are present and precise. The remaining gap is the unexplained filters object, which for a capture tool is the main selection surface.

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 0% and the tool has a nested filters object with date, event_ids, sport_ids and affiliate_ids, none of which the description explains (formats, cardinality caps, mutual constraints). The '50 messages' and 'five seconds' language loosely maps to max_frames and duration_ms, but the primary required parameter is left entirely opaque.

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?

States a specific verb (read) and resource (actual frames from the V1 WebSocket), scoped to selected events and books. It explicitly distinguishes itself from the V2 market tools and the other capture_* siblings by naming the legacy line contract it serves.

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?

Gives an explicit when-not ('use only for legacy line contracts; prefer V2 market tools') and a hard prerequisite (eligible WebSocket access with all periods, live/player-prop access, no delay), plus the fallback for restricted plans (REST). An agent can route correctly without opening any schema.

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