Gild Card

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

Annotations already indicate this is a non-read-only, non-destructive mutation, and the description adds meaningful behavioral context: golden cards are highlighted and become filterable via indexed_by='golden'. This goes beyond the structured annotations by describing the persistent effect of the action. It doesn't mention idempotency or the reverse operation, but the core behavior is transparent.

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 two sentences with no wasted words. The core action is first, followed by the useful consequence and a concrete usage recommendation. Every sentence earns its place.

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 simple two-parameter mutation with robust schema descriptions and non-destructive annotations, the description covers what the tool does, why it matters, and how it interacts with another tool. It lacks only minor details such as behavior when a card is already gilded, but nothing critical is missing for correct invocation.

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?

The input schema already provides 100% coverage with detailed descriptions for both account_slug and card_number, including the distinction between card_number and card_id. The tool description adds no parameter-level meaning beyond that, so the baseline score of 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?

The description uses a specific verb and resource: 'Mark a card as golden (priority/important).' It clearly explains what the operation does, differentiates the card's golden state from normal cards, and connects it to the filtering capability in fizzy_get_cards. This is unambiguous and distinct from the sibling 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?

The description gives clear usage context: 'Use this to flag high-priority work items.' It explains the practical effect (highlighting and filtering) but does not explicitly state when not to use it or mention the alternative ungild_card. Still, the guidance is sufficient for an agent to understand when this tool is appropriate.

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