nexus_fanout

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

The description mentions a key behavioral trait: concurrency limit. It also implies that the command is executed per item. With only openWorldHint as an annotation, the description adds some useful context beyond annotations. However, it does not disclose other important behaviors such as whether the tool blocks until completion, returns output, or has side effects. The transparency is adequate but not rich.

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 a single concise sentence, front-loaded with 'Parallel map' to immediately convey the core concept. There is no redundant or extraneous text. Every word earns its place.

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 tool with moderate complexity (command template, items, concurrency, timeout) and no output schema, the description gives a good high-level overview but omits critical details like return values, error handling, and whether execution is synchronous or asynchronous. These gaps are significant for an agent deciding how to use the tool correctly. The description is adequate for basic understanding but incomplete for full guidance.

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 only 50%, so the description needs to compensate. 'concurrency limit' adds meaning to the concurrency parameter beyond its schema (which only has min/max/default). The phrase 'run a command over multiple items' helps clarify the items and command parameters. However, timeoutMs is not mentioned, and the description does not fully compensate for the missing schema descriptions. It provides some additional semantics but not a complete picture.

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 what the tool does: 'Parallel map: run a command over multiple items with concurrency limit.' It uses a specific verb ('run'), identifies the resource ('command over multiple items'), and distinguishes it from likely siblings like nexus_exec (which probably runs a single command) by emphasizing parallel fan-out. This is a specific and differentiating purpose statement.

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 gives clear context for when to use the tool: when you need to run a command over multiple items in parallel. The label 'Parallel map' implies a batch-processing scenario. However, it does not explicitly mention when not to use it or name alternatives (e.g., nexus_exec for single commands), so it falls short of a 5. Still, the context is clear and implied.

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