Custom Attributes: List all custom attributes in an account

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuinely useful behavioral context an agent would not otherwise have: the required 'User API key' header auth and the note that text values may arrive in Persian/other scripts with Persian/Arabic-Indic digits, which matters for downstream parsing.

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 core purpose and auth are front-loaded, but the raw REST endpoint line and especially the Persian/Arabic-Indic digit note read as copy-paste boilerplate that is tangential to a read-only listing call. The definition carries sentences that do not fully earn their place for this operation.

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 read-only listing tool with no output schema, the description covers auth and data encoding but never says what the response contains (e.g., the list of definitions and their fields) or whether results are paginated. Adequate but with a visible gap.

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%, so both account_id and attribute_model are already documented in the schema, and the description adds nothing about attribute_model's 0/1 semantics. Per the rubric, a baseline of 3 is correct when the schema does the heavy lifting.

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 gives a specific verb ('List') and resource ('custom attribute definitions in the account'), which clearly separates it from the get/add/update/remove custom-attribute siblings. It is clear and unambiguous, though it does not explicitly name which sibling to use instead.

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 implies retrieval of all definitions but offers no explicit when-to-use, when-not-to-use, or alternative guidance. It never mentions gapify_get_custom_attribute for single lookups or gapify_list_custom_filters as a related listing tool.

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