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

Goes beyond the readOnly/idempotent annotations by disclosing a hard content gate (never Mature) and the no-match contract (game: null, code NO_MATCHES, and automatic filter relaxations). The relaxation behavior is the most important trait an agent needs, but it is left vague about which filters get relaxed and in what order.

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, front-loaded with the core action and no filler. The final sentence packs edge-case behavior efficiently, though terms like 'relaxations' and 'NO_MATCHES' are used as jargon without framing.

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, so return shape needn't be explained, and the no-match case is covered. But for a 12-parameter tool, the non-enum parameters (min_quality, session_length_max, include_listing_only) and the interaction between 'never returns Mature' and content_rating_max='mature' are unexplained, leaving real ambiguity.

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 only 17%, so the description must carry the burden and does not: the only parameter it touches is seed, which the schema already documents. Ten filtering parameters (mood, genre, players, difficulty, min_quality, exclude_genres, content_rating_max, session_length_max, include_listing_only, inputs) get no semantics beyond self-evident enums.

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 and resource ('One random eligible game') plus the flow it serves ('surprise me') and the seed-determinism variant. This is clearly distinguishable from search_games and games_like, which return filtered or similar lists rather than a single sampled pick.

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 clear usage context ('surprise me' flows) and a decision rule for the seed parameter (deterministic pick). It never names search_games or games_like as the alternative for explicit criteria, so the when-not-to-use case is left implicit.

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