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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's job is to add behavior beyond that—which it does: a hard 20-result cap, the returned fields, and the sort order (affected count desc, then name). It stops short of noting truncation implications or rate limits, so not a 5.

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 sentences, zero filler, with the matching purpose front-loaded and the return shape second. Every clause carries 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?

An output schema exists, so return values needn't be explained, yet the description still summarizes them without bloat. Matching semantics, result cap, and ordering are all covered; only the truncation consequence of the 20-cap goes unstated.

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%, so baseline is 3, but the description adds genuinely new semantics: matching is case-insensitive and substring-based, which the schema's 'Part of the operator name' does not state. The 'up to 20' line also corroborates the limit parameter's maximum.

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 and resource ('Finds operators'), the matching rule (substring, case-insensitive) and the data domain (Railroad Commission of Texas). It does not name or contrast with its closest sibling screen_operators, so an agent must infer the boundary between search and screen.

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?

Usage is implied by the substring-matching semantics, but there is no explicit when-to-use, when-not-to-use, or named alternative such as screen_operators or list_operator_wells. The agent has to reason from the name.

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