expand_node

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 effectively describes key behaviors: 'Read-only; no writes except an implicit positive feedback row if called within 10 min of a matching query_chains. Returns up to 3 matched source nodes × up to 10 neighbours (edges with score ≥ 0.08), plus a `stale_warning` field — call `rescan` if non-null.' This covers safety (read-only with one exception), output structure, and side effects, though it could mention error handling or rate limits.

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 appropriately sized and well-structured, with the first sentence stating the core purpose and subsequent sentences providing usage guidelines and behavioral details. Every sentence adds value, though it could be slightly more front-loaded by moving key behavioral traits earlier.

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 no annotations and no output schema, the description does a good job of covering the tool's complexity. It explains purpose, usage, behavior, and output structure. However, it could be more complete by explicitly mentioning the tool's return format (e.g., JSON structure) or potential error cases, which would help an AI agent better handle responses.

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 100% description coverage, so the baseline is 3. The description adds valuable context beyond the schema: it explains that 'Partial, case-insensitive match against node id and raw_name; ambiguous inputs return multiple source groups,' and clarifies the relationship to 'query_chains' results. This enhances understanding of how the parameter is used, though it doesn't introduce new parameter-specific details.

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: 'One-hop neighbours of a known node... with similarity scores and file paths.' It specifies the verb ('expand') and resource ('node'), and distinguishes it from sibling 'query_chains' by noting it's for tracing 'one hop further' after having a concrete node name.

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 explicit usage guidance: 'Use AFTER query_chains when you already have a concrete node name and want to trace one hop further. Use query_chains (not this) when starting from a business term or when you don't yet know a node name.' It clearly defines when to use this tool versus the alternative 'query_chains'.

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