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 states it's a listing operation, implying read-only behavior, but doesn't cover critical aspects like permissions needed, rate limits, pagination, or what 'active sessions' entails. This leaves significant gaps for an agent to understand the tool's behavior fully.

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 extremely concise and front-loaded, consisting of just two clear sentences that directly state the tool's function and parameter use. There is no wasted verbiage, making it efficient for quick understanding.

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 low complexity (one optional parameter) and the presence of an output schema (which handles return values), the description is somewhat complete. However, with no annotations and incomplete parameter guidance, it lacks depth for a full understanding, especially regarding behavioral context and usage relative to siblings.

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 description adds some meaning by explaining that 'keyword' is used for filtering, which is not covered in the schema (0% coverage). However, it doesn't detail the keyword's format, case-sensitivity, or matching criteria. With one parameter and low schema coverage, the description compensates partially but not fully.

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's purpose with a specific verb ('List') and resource ('active sessions'), and mentions optional filtering. However, it doesn't explicitly differentiate from sibling tools like 'nexo_session_diary_read' or 'nexo_agent_list' that might also involve session-related operations, keeping it from a perfect score.

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 mentioning filtering 'if provided,' but lacks explicit when-to-use instructions, prerequisites, or alternatives compared to siblings. No context on when to choose this tool over others like 'nexo_agent_list' or 'nexo_session_diary_read' is given.

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