od_cost_matrix

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

With no annotations, the description carries full burden. It only states a requirement but does not disclose mutation behavior, overwrite behavior, or other side effects. The parameter 'overwrite' exists in schema but is not mentioned.

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 concise sentences with front-loaded purpose. Could be improved by adding more detail, but no wasted words.

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?

Despite having a complex input schema (7 properties) and many sibling tools, the description provides only a bare-bones purpose and a single prerequisite. Lacks essential context for proper tool selection and usage.

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%, requiring the tool description to compensate. However, it adds no information about any of the 7 nested parameters, leaving them entirely unexplained.

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 creates an origin-destination cost matrix, referencing the underlying function (MakeODCostMatrixAnalysisLayer). It distinguishes from sibling tools like route_analysis or closest_facility by name and specific purpose.

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?

Only mentions a prerequisite (Requires Network Analyst) but gives no guidance on when to use this tool vs alternatives like route_analysis, service_area, or closest_facility.

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