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

Annotations already indicate read-only, idempotent, non-destructive behavior, and the description aligns with that. It adds valuable conditional behavior: writable entities also get save/delete field info, while write-only entities like operatorSettings only get the save-related fields. This goes beyond what annotations provide.

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 tightly written sentences with no filler. The main purpose is front-loaded, and the conditional behavior is stated compactly. Every clause earns its place.

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-only describe tool with no output schema, the description fully covers what the tool returns: filterable fields, enum values, save() fields, delete() refusal fields, and the write-only exception. Nothing essential is missing for an agent to invoke it correctly.

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% for the single entity parameter, so the baseline is 3. The description adds meaning beyond the schema by explaining entity categories ('writable entity', 'write-only entity'), giving operatorSettings as an example, and tying the parameter to RSQL filtering and save/delete behavior.

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 opens with a specific verb and resource: 'List the filterable fields (and enum values) for a query dataset.' It states the purpose ('so you can build a valid RSQL filter') and further distinguishes itself by covering save() accepted fields and delete() refused fields, making it clear how this differs from sibling describe tools.

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 gives clear usage context: use it to construct RSQL filters for query datasets, and for writable entities to learn what save() and delete() accept or refuse. It does not explicitly name alternatives or say when not to use it, but the intended scenarios are well implied.

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