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

Annotations already provide readOnly/idempotent/destructive hints. The description adds a behavioral boundary ('does not assess condition') and clarifies the input dependency, which is useful. It doesn't over-explain since annotations cover safety.

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 description is concise and front-loaded with the trigger phrase. It lists outputs in a single sentence, which is informative without being bloated. Could be slightly tighter but each sentence carries weight.

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 read-only analytical tool with two parameters and an output schema, the description provides all essential context: when to invoke, what it returns, prerequisite, and a key limitation. Nothing an agent needs to call it correctly is missing.

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 both parameters are fully described. The tool description repeats the 'card id from search_cards' requirement, adding no new parameter semantics. 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 opens with a specific trigger ('when the user asks whether a card is worth grading...') and names the submission companies. It clearly distinguishes itself by noting it does not assess condition of the user's copy, separating it from condition-appraisal tools.

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 explicit when-to-use context: when the user asks about grading a specific card or PSA 10 premium. It states a prerequisite (requires a card id from search_cards) and an exclusion (does not assess condition). However, it doesn't name sibling alternatives like best_cards_to_grade for multi-card comparisons.

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