Get Month

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful context about what data is included and that values are in dollars, making the tool's behavior more concrete than the annotations alone.

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?

Two sentences, no filler. The first sentence front-loads the core purpose and return contents; the second adds use-case guidance and a pointer to the relevant sibling tool.

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 tool with an output schema, two well-documented parameters, and annotations covering safety and idempotency, the description is complete. Nothing an agent needs to know before calling it is missing.

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 covers both parameters (month and budgetId) with clear descriptions, so the schema already does the heavy lifting. The description adds a high-level sense of what the month returns but does not add meaning beyond the schema for individual parameters.

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 states a specific verb and resource ('Get one budget month's detail') and enumerates exactly what is returned: month totals plus every category's budgeted/activity/balance and goal fields. It also distinguishes itself from sibling tools like get_month_category and get_overspent_categories by clarifying it returns the full month picture.

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?

It explicitly identifies when to use the tool ('workhorse for monthly reviews and budget-vs-actual questions') and points to a specific alternative for a narrower need ('combine with get_overspent_categories for the negative balances only'). This gives an agent clear routing guidance.

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