opensearch_stats

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

With no annotations provided, the description discloses that the tool errors gracefully on non-numeric fields, implying safety. It does not cover other behaviors like performance or pagination, but the output schema exists to describe return values.

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 two paragraphs: first states purpose and constraint, second details error handling and alternative. Every sentence adds value, and it is front-loaded with the essential information.

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 simple stats tool with full schema coverage and an output schema, the description covers the numeric constraint, error behavior, and alternative tool. It provides sufficient context for correct agent usage.

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 coverage is 100%, baseline 3. The description adds critical context: the field must be numeric and provides example formats ('rule.level', 'data.bytes'), which is not evident from the schema alone.

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?

Description clearly states the tool computes min/max/avg/std for a numeric field, with a specific verb and resource. It distinguishes itself from opensearch_terms by noting the alternative for keyword fields.

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 the tool only works on numeric fields, warns of a 400 error for text fields, and recommends opensearch_terms for keyword fields. This provides clear when-to-use and when-not-to-use guidance.

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