NEXO Brain

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

No annotations are provided, so the description carries full burden. It states the tool logs decisions but doesn't disclose behavioral traits such as where the log is stored (e.g., database, file), whether it's idempotent, if it requires authentication, or what happens on failure. The description is basic and misses critical operational context for a logging tool.

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 that front-loads the core purpose without unnecessary words. Every part ('Log a non-trivial decision with reasoning, alternatives, and evidence') contributes directly to understanding the tool's function, making it highly concise and well-structured.

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's moderate complexity (8 parameters, 2 required) and the presence of an output schema (which reduces need to describe returns), the description is minimally adequate but incomplete. It covers the basic purpose but lacks details on parameters, behavioral traits, and usage context, leaving gaps for effective tool invocation despite the output schema support.

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 schema provides no parameter details. The description mentions 'reasoning, alternatives, and evidence', which loosely maps to parameters like 'decision', 'alternatives', and 'based_on', but doesn't explain any of the 8 parameters (e.g., 'domain', 'confidence', 'review_days') or their formats. It adds minimal value beyond the parameter names.

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 action ('Log') and the object ('a non-trivial decision'), specifying what information to include ('reasoning, alternatives, and evidence'). It distinguishes from sibling tools like 'nexo_decision_outcome' or 'nexo_decision_search' by focusing on logging rather than outcome recording or searching. However, it doesn't explicitly contrast with these siblings in the description text.

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 minimal guidance by specifying 'non-trivial decision', implying a threshold for usage, but offers no explicit when-to-use rules, prerequisites, or alternatives. It doesn't mention when to choose this over other decision-related tools like 'nexo_decision_outcome' or general logging tools, leaving the agent with little contextual direction.

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