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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds a genuinely non-obvious behavioral trait: field names are case-sensitive and wrong names are silently ignored — a failure mode an agent could not infer from annotations. It stops short of auth or rate-limit context, 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, front-loaded with the returned fields, followed by the usage rule and the silent-failure caveat. The trailing GET path is compact and useful for debugging; nothing is wasted.

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?

One required parameter, read-only annotations, and no output schema — the description compensates by enumerating the shape of the returned field metadata, which is exactly what an agent needs before relying on the response.

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 100%, and the schema already states the table name must match what method_list_tables returns, with the regex pattern and examples. The description adds no format or naming detail beyond that, so baseline 3 applies.

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+resource ('The exact field names of a table') and enumerates the metadata returned (type, required, creatable, mutable, dropdown reference table). It is clearly distinguishable from the sibling method_list_tables, which returns tables rather than fields.

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?

Explicitly says when to use it: to pick `select` fields and to supply field names in create/update calls. It does not name the alternative tool to call for a different need, but the usage context is concrete enough that an agent knows the trigger condition.

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