List Pinned Cards

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

Annotations already mark readOnlyHint=true and destructiveHint=false, but the description adds valuable behavior beyond that: non-paginated, at most 100 pins, plain array return, and a warning about potentially several-megabyte payloads with default fields. No contradiction with annotations.

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 front-loaded with the core purpose, then covers constraints, performance, and alternatives in logical order. Every sentence adds actionable information; the length is justified by the value it provides.

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, non-paginated listing tool, the description covers return shape, limits, performance, field selection, and related tools. No output schema exists, but the description sufficiently explains what to expect without needing to document card object internals.

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 already documents both parameters fully (100% coverage), but the description adds meaning by strongly recommending fields='summary' and quantifying size differences (4x to over 100x smaller). It also clarifies account_slug format and how to discover valid slugs via fizzy_get_identity/fizzy_get_accounts.

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: 'Get the cards the current user has pinned in an account, as a plain array of cards.' It clearly defines scope (per-user, per-account) and is easily distinguished from siblings like fizzy_pin_card and fizzy_get_card.

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?

Explicitly advises when to prefer fields='summary', tells the agent to call fizzy_get_card for full detail of a specific pin, and names fizzy_pin_card/fizzy_unpin_card as the tools for changing the list. This is direct when-to-use vs. alternative guidance.

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