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

Annotations already flag this as a non-read-only, non-idempotent write, and the description adds genuinely new context beyond them: the 5-new-sessions-per-minute-per-account rate limit and the fact that an ID is returned. It does not say what happens when the limit is exceeded (error vs. queue), which keeps it below a 5.

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?

Two tight clauses with the action and the limit front-loaded, and no filler. Slight redundancy between 'creates a new practice session record' and 'when a game starts in the interface', but nothing that warrants trimming for correctness.

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?

With an output schema present, the return value need not be detailed, yet the description still notes the ID. For a one-parameter tool with full schema coverage, the only meaningful gap is the absence of workflow context tying it to the sibling tools that open and save games.

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 100% and the single 'game' parameter has a fully enumerated set of slugs documented in-schema. The description adds no syntax, format, or defaulting information beyond that, so the baseline 3 applies.

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?

Uses a specific verb and resource: creates a new practice session record for the connected user and returns its ID. It is distinguishable from siblings like get_game_results or save_game_result, though it never explicitly contrasts itself with open_hirevue_game, which an agent might reasonably confuse it with.

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 phrase 'when a game starts in the interface' implies the trigger condition, but there is no explicit ordering guidance relative to open_hirevue_game or save_game_result (e.g. whether the returned ID is required by the latter). Usage is implied rather than stated.

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