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

With no annotations, the description carries the full burden, and it does substantial work: it explains the output shape (companies, printed name, first-seen, read date), that each row is a dated quote from a company's published page, that it is read-only in nature, and that reuse is legally restricted. It does not cover rate limits or error behavior, but it is far more transparent than a minimal read-tool description.

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 longer than typical but every sentence carries useful information: what is returned, the one-per-call constraint, citation requirements, and licensing restrictions. The core behavior is front-loaded before the legal notice, and nothing is purely filler.

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?

For a single-parameter read tool with no output schema and no annotations, the description explains the return semantics, the data source, and the permitted use well enough for an agent to call it correctly. It lacks an example or explicit no-match behavior, but those are minor gaps given the simple input schema.

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 already describes the single subprocessor parameter with 100% coverage ('its name, an alias, or its id here'). The tool description adds 'One subprocessor per call' but does not enrich parameter semantics beyond the schema, so the schema-heavy baseline of 3 is appropriate.

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 identifies the resource (companies' published subprocessor lists) and the specific operation: mapping a subprocessor to the companies that name it, plus the name printed, first-seen date, and read date. It does not explicitly distinguish itself from siblings like as_of, changes, or in_chain, so it lacks full sibling differentiation.

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 usage constraints ('One subprocessor per call', 'Free to read, cite and link') but never says when to use this tool versus alternatives such as list, resolve, or changes. There is no when-to-use or when-not-to-use guidance relative to sibling tools.

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