Get Budget Snapshot

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds the month scoping and content areas but does not disclose behavioral traits such as caching, refresh behavior, or return format. Since annotations handle the main safety context, a score of 3 is appropriate, consistent with examples where the description adds some value but not rich behavioral detail.

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 a single, well-structured sentence that front-loads the main purpose and lists the key output components. Every phrase adds value without redundancy. It is concise and immediately informative.

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?

Despite lacking an output schema, the description gives a reasonable outline of the expected return content ('month details, account totals, and category highlights'), which is sufficient for a snapshot tool. Combined with solid annotations and full schema coverage, the context is fairly complete, though it could have clarified the refresh/TTL behavior beyond the schema parameter description.

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%, with each parameter (month, plan_id, refresh) clearly documented. The tool description itself adds minimal parameter meaning beyond the schema, only reinforcing the 'given month' aspect. With high schema coverage, the baseline of 3 applies; the description does not compensate further.

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 function with a specific verb ('Get') and resource ('a high-level snapshot of a YNAB plan for a given month'), and lists the included aspects (month details, account totals, category highlights). This distinguishes it from sibling tools like ynab_list_accounts or ynab_list_categories, which provide detailed lists rather than a combined snapshot.

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 appropriate usage: when seeking a high-level monthly summary rather than granular details. It does not explicitly mention alternatives or when-not-to-use, but the phrase 'high-level snapshot' and the month scoping provide clear context. No exclusions are stated, but the sibling tool names hint at more detailed options.

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