map_reduce_mr_reduce

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

With no annotations, the description must disclose behavioral traits. It only states the operation and lists options without explaining edge cases (e.g., empty data, missing field) or side effects. The 'separator' parameter is not described, and the behavior of 'join' or other operations is left implicit.

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 concise (two sentences, no extraneous words) and front-loaded with the core action. However, the brevity sacrifices critical details, causing a trade-off between conciseness and completeness.

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?

Given the tool has 4 parameters with 0% schema coverage and no annotations, the description is insufficient. It does not specify data format, field referencing, separator usage, or behavior on empty/null inputs. An output schema exists but does not compensate for missing parameter context.

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 0%, so the description must compensate for parameter semantics. It only lists possible operations but does not explain 'data' (expected format, e.g., JSON array), 'field' (how to reference fields), or 'separator' (usage with 'join'). The description adds virtually no meaning beyond the schema structure.

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 'Reduce a list to a scalar' and lists valid operations, distinguishing it as the sole reduce tool in the map_reduce group. However, it does not specify how the 'data' and 'field' parameters are used, leaving ambiguity about the expected input format.

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?

No guidance on when to use this tool versus other reduce tools (e.g., batch_batch_reduce) or alternative approaches. There are no examples, prerequisites, or exclusions, making it difficult for the agent to decide when this tool is appropriate.

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