ynab_set_default_budget

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

Annotations indicate idempotency and non-destructiveness. The description adds that the tool validates against the YNAB API, returns specific fields (success, default_budget_id, cache_warm_started), and lists possible errors. 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 structured with sections (Args, Returns, Examples, Errors) and is concise. Every sentence adds value without redundancy.

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?

Given the tool's simplicity (1 parameter) and presence of annotations and output schema, the description covers all essential aspects: purpose, parameter, return values, and error handling.

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 has no description coverage (0%), but the description adds meaningful details: 'budget_id (string, required): Budget UUID to set as default. Validates against YNAB API.' This clarifies the format and behavior beyond the schema.

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 clearly states the tool's action: 'Set a default budget so other tools don't require budget_id every call.' It specifies the verb (set), resource (default budget), and distinguishes it from siblings like ynab_get_default_budget.

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 explains when to use it (to avoid passing budget_id every call) and provides an example of obtaining the budget_id from ynab_list_budgets. It does not explicitly state when not to use it, but the context is clear.

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