9router fanout

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

Annotations are all false and do not disclose read-only, idempotent, or destructive nature. The description does add behavioral context: 'parallel (max 6)' reveals concurrency and a hard limit. It does not disclose potential costs, rate limits, error behavior, or whether results are aggregated, but the output schema may cover return structure.

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 short sentences with no filler, placing the core action and constraint upfront. It is efficient but could have packed more useful information without bloating, such as a note on result shape or model validity.

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?

With five parameters, no schema descriptions, and an output schema present, the description covers the essential parallel-fanout idea but omits guidance on valid models, what happens if more than 6 are requested, how outputs are returned, and meaning of timeout/max_tokens. The existence of related tools like nine_providers and nine_combos suggests more context is needed for correct tool selection and invocation.

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 0%, so the description must compensate. It only clarifies 'models' as the N in 'N models' and 'prompt' as the shared prompt, which are fairly inferable from the parameter names. System, max_tokens, and timeout_seconds are left entirely undocumented in both schema and description, adding little semantic value.

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 uses a specific verb phrase 'Same prompt to N models in parallel' and identifies the resource as a fanout primitive, which clearly distinguishes it from sibling models like nine_chat. However, it does not explicitly contrast with nine_chat or other nine_* tools, leaving some differentiation to inference.

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 phrase 'Judge/ensemble primitive' hints that the tool is intended for tasks requiring multiple model outputs for comparison or aggregation, but it does not explicitly state when to use it versus alternatives like nine_chat or nine_combos. The usage context is implied rather than stated.

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