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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds real value beyond them: result cap of 5, best-first ordering, disclosure of match signals, and a stated cost of 1 credit — the credit cost is exactly the kind of operational detail annotations cannot convey.

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?

One dense sentence with the resource and input flexibility front-loaded, followed by the result contract and cost. No filler or repetition of schema content.

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?

For a 3-parameter read tool with no output schema, the description covers input domain, result cap, ordering, and cost. The one meaningful gap is the no-match / low-confidence case — an agent doesn't know whether to expect an empty list, a single forced best guess, or a confidence threshold.

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%, making 3 the baseline, but the description genuinely enriches the query parameter by stating that fields can appear in any order and that typos are tolerated — neither of which the schema says. It still doesn't clarify how the game/language filters interact with a query that embeds a language token.

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?

Specific verb+resource ('Identify a card from free text') with a clear statement of input flexibility (name, number, edition, language, any order, typos tolerated) and output shape (up to 5 candidates, best first, with matched signals). It implicitly separates itself from structured siblings like search_cards, but never names an alternative explicitly.

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 free-text, typo-tolerant framing implies this is the tool for messy human input rather than structured lookups, but there is no explicit 'use this instead of search_cards when...' guidance and no stated exclusions or prerequisites. An agent must infer the routing decision from the sibling names alone.

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