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

Annotations only establish read-only/idempotent safety; the description adds substantive behavioral context beyond that: tamper-evidence of the append-only log, the requirement that every failing check cite the clause it enforces, and an explicit disclaimer that verdicts are readiness signals and never a legal compliance determination. That last point materially changes how an agent should report results.

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 core capability is front-loaded in the first sentence, with usage questions and the compliance caveat following. It is dense but every sentence carries weight; the capitalized warning is emphatic rather than redundant, though the description runs slightly long for a two-parameter read tool.

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?

With no output schema, the description does the work of describing the response shape (custody hops, tamper verdict, clause-cited check results, embedded disclaimer), which is enough for an agent to interpret results. It omits any mention of pagination or result-size limits for what could be a long custody history.

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 coverage is 100% and both parameters are documented there, including the find_unit prerequisite. The description's mention of "DSCSA / the EU passport rules" loosely maps to the pack parameter's values but adds no syntax or format detail, so the schema is doing the heavy lifting — baseline 3.

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 names a specific resource (one serialized unit's full history) and enumerates exactly what it returns: custody hops from commissioning to dispensing, append-only log tamper status, and per-regulation verdicts. This is clearly separable from siblings like chain_readiness, dpp_readiness, and find_unit.

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?

It gives concrete triggering questions ("where has this been", "who handled it", "is its record trustworthy", "does this unit pass DSCSA / the EU passport rules") and the schema tells the agent to use find_unit first when only a scan is available. It stops short of naming sibling alternatives or stating when not to use it (e.g., vs. chain_readiness).

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