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 mentions what metrics are retrieved but doesn't disclose behavioral traits like whether this is a read-only operation, if it requires authentication, potential rate limits, or what the output format looks like. For a stats tool with zero annotation coverage, this leaves significant gaps in understanding how the tool behaves.

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 key information ('Cognitive memory system metrics') and specifies the metric types without any wasted words. Every part of the description earns its place by clarifying what the tool provides.

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 complexity (stats retrieval with no inputs) and the presence of an output schema (which handles return values), the description is adequate but incomplete. It specifies what metrics are retrieved but lacks context about behavioral aspects (e.g., read-only nature, permissions). With no annotations and an output schema, the description should ideally mention that it's a safe read operation or other usage notes.

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 tool has 0 parameters with 100% schema description coverage, so the schema already fully documents the input (none required). The description doesn't need to add parameter information, and it appropriately doesn't mention any parameters. The baseline for 0 parameters is 4, as the description correctly focuses on the tool's purpose rather than nonexistent inputs.

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 retrieves 'cognitive memory system metrics' and specifies the types of metrics (STM/LTM counts, strengths, retrieval stats). It distinguishes from siblings like 'nexo_cognitive_metrics' by focusing on memory system stats rather than general cognitive metrics. However, it doesn't explicitly state the verb (e.g., 'retrieve' or 'get'), which prevents 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 no guidance on when to use this tool versus alternatives like 'nexo_cognitive_metrics' or 'nexo_cognitive_inspect'. It doesn't mention prerequisites, timing considerations, or any explicit 'when' or 'when not' scenarios. The agent must infer usage from the tool name and description alone.

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