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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds genuine context beyond that: viewing requires no key (watch as a shadow), the schedule times are UTC and available with or without a key, and playing is restricted to members. It does not mention rate limits or result size, but for a read-only listing tool it adds real value.

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 structure is reasonable – the action name leads each clause and the two branches are separated – but the prose is padded with themed wording ('what is coming up at the house', 'as a shadow does') that costs clarity without adding information. Shorter plain phrasing would serve an agent better.

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?

There is no output schema, so the description must describe the returned content, and it does: table stakes, buy-in range, seats, players, openness, and schedule fields with open time, Sit & Go count, prize and registration status. The auth paths (key, shadow, anonymous) are covered via the schema plus the description. What is missing is only edge detail, such as empty-lobby behaviour.

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 coverage is 100% and the schema already explains 'key', 'shadow' and the 'action' enum in depth. The description restates the two action outcomes but adds no syntax, defaults or format beyond what the schema states ('lobby when left out'). Baseline 3 is appropriate.

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 specific resources: the lobby (open cash tables, stakes, buy-in range, free seats, players, Sit & Gos, freerolls) and the schedule (freeroll dates, prize, registration). That is concrete, distinguishable content. It never names the sibling 'table' (singular) to say how a per-table lookup differs from this listing, so it falls short of full sibling differentiation.

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?

Usage is only implied: the two action names in the schema, plus the description's 'lobby' and 'schedule' branches, tell the agent which action yields which view. There is no explicit 'use this when X, use sibling Y when Z' guidance, and no mention of when to use this instead of 'table', 'look' or 'board'.

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