NEXO Brain

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It implies a write operation ('record'), suggesting mutation, but doesn't specify permissions needed, whether changes are reversible, rate limits, or what the output looks like. This is a significant gap for a tool that appears to modify data.

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, efficient sentence with no wasted words. It's appropriately sized and front-loaded, clearly stating the tool's purpose without unnecessary elaboration.

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 that there's an output schema (which reduces the need to describe return values) but no annotations and low parameter coverage, the description is minimally adequate. It states what the tool does but lacks details on behavior, parameters, and usage context, leaving gaps for a mutation tool.

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?

The input schema has 0% description coverage, so parameters 'id' and 'outcome' are undocumented. The description doesn't add any meaning beyond the schema—it doesn't explain what 'id' refers to (e.g., decision ID) or what format 'outcome' should be in. With low schema coverage, the description fails to compensate adequately.

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 'Record what actually happened after a past decision' clearly states the tool's function with a specific verb ('record') and target ('what actually happened after a past decision'), but it doesn't distinguish this from sibling tools like 'nexo_decision_log' or 'nexo_decision_search'. The purpose is understandable but lacks sibling differentiation.

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 provides no guidance on when to use this tool versus alternatives. There are sibling tools like 'nexo_decision_log' and 'nexo_decision_search' that might overlap in functionality, but the description doesn't mention them or specify prerequisites, exclusions, or appropriate contexts for use.

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