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

Annotations already declare readOnlyHint, idempotentHint, and closed-world behavior, so safety is covered. The description adds almost nothing beyond that: no pagination behavior, no relevance ranking, no hint about how partial matches behave. It does state the return shape briefly, but that is thin for a search tool with no output schema.

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?

Two tight sentences, front-loaded with the scope and purpose. No filler. Not quite a 5 because the second sentence is doing double duty as both return description and field list, slightly compressing two jobs into one clause.

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?

Covers search scope and return fields, but with no output schema and no guidance on search semantics (fuzzy matching, case sensitivity, ranking) or pagination via limit, an agent still has gaps. The description is complete enough to call the tool but not to predict its behavior.

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 100%, so parameters are already fully documented. The description adds the notion that 'query' can match code, system, dashboard light, or symptom words, which is useful beyond the schema's generic 'Code or free text to search for.' This is a modest value-add, so baseline 3 holds.

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?

States a specific verb (full-text search), resource (DERATE's public diesel truck fault-code library), and searchable axes (code, system, dashboard light, symptom words). Distinguishes itself from siblings like list_fault_codes and get_truck_fault_code by being a free-text search rather than a lookup or list.

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?

Mentions searchable fields, which implies when this tool is useful, but does not explicitly say when to use it instead of list_fault_codes, buscar_codigo, or get_truck_fault_code. No exclusions or prerequisites are stated. Adequate but leaves routing to inference.

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