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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, which covers the safety profile. The description adds the date-range scoping and return-type context (observations). It doesn't disclose pagination behavior, error handling, or whether data is daily/monthly frequency, but with strong annotations the bar is lower.

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?

A single, tightly-written sentence that conveys the core action (return observations), the object (one economic indicator), and the key option (optional dates). Zero waste, appropriately front-loaded.

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?

This is a simple data-retrieval tool with strong annotations (readOnly, idempotent) and an output schema. For this complexity level, the description adequately covers the main behavior. It could mention return format or frequency but the output schema covers returns. Minor gap: no mention of how limit interacts with date ranges or max date range size.

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 50%. The 'name' parameter has an example (CPI) in the schema. The description mentions 'optional dates for the observation period' which aligns with start_day/end_day. However, it doesn't clarify the relationship between limit and date filtering, or default behavior when no dates are provided, leaving the other 50% of parameters partially undocumented.

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 it returns observations for one economic indicator, with optional date filtering. The verb+resource ('Return observations...') is specific. However, it doesn't explicitly distinguish from siblings like macro_calendar or macro_current_conditions, which could be confused with this tool, so it's not a 5.

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 usage for fetching historical indicator observations with date ranges, but provides no explicit when/when-not guidance or alternatives. Siblings like macro_current_conditions exist but aren't referenced, leaving the agent to infer which tool fits current-vs-historical data needs.

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