Read standard PIDs

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

The description adds that only fixed, centrally allowlisted PIDs are accepted and arbitrary commands are rejected, which supplements the annotations (readOnlyHint, idempotentHint, destructiveHint) with specific constraints.

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 sentence that directly conveys the tool's purpose and constraints with no superfluous information.

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?

The description covers the main behavioral aspect but omits parameter semantics. Given the presence of an output schema, return values need not be explained. Minor gap: default behavior when pids is null.

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?

With 0% schema description coverage, the description fails to clarify the parameters. It does not explain the format of 'pids' (e.g., that they are hex codes like 010C) or the role of 'vehicle_id'.

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 it reads Mode 01 PIDs from a specific allowlist, distinguishing it from sibling tools like obd_read_dtcs or obd_read_ecu_snapshot.

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 indicates the tool is for reading only standard allowlisted PIDs and not arbitrary commands, providing implicit usage context. It does not explicitly name alternatives or when-not to use.

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