Calculate Financial Runway

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the agent knows this is a safe, repeatable calculation. The description adds valuable context about the 'survival mode' calculation variant, which goes beyond what annotations provide. No contradictions 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?

Three sentences that are front-loaded with core functionality, followed by usage guidance. Every sentence earns its place: first defines the calculation, second adds the survival mode variant, third provides usage scenarios. No wasted words.

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 calculation tool with comprehensive annotations (read-only, non-destructive, idempotent) and full schema coverage, the description provides adequate context about what the tool does and when to use it. The main gap is lack of output schema, but the description implies the output will be months-based calculations.

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 all parameters are well-documented in the schema itself. The description doesn't add significant parameter-specific details beyond what's already in the schema descriptions. Baseline 3 is appropriate 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 clearly states the tool calculates 'Financial Runway' with specific details: 'how many months you could survive without any income based on your savings and monthly expenses' and includes 'survival mode' runway. It distinguishes from siblings by focusing on this specific personal finance metric rather than budgeting, net worth, or savings planning tools.

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 states 'Use this when someone asks how long their savings would last, how much emergency fund they need, or whether they have enough saved.' This provides clear scenarios for when to invoke this tool versus alternatives like calculate_net_worth or plan_savings_goal.

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