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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered; the description adds useful context beyond that: authentication via the One U Education account, the declared planning scope requirement, the guarantee that credentials and identity are never tool arguments, and caching expectations across calls at the same schema name/version. It does not describe error or empty-result behavior, but with annotations and an output schema in place this is a minor gap.

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 instruction (discover fields, omit index_ref for root) is front-loaded, and each subsequent sentence carries a distinct rule about navigation, batching, caching, or exclusions. The clipped imperative style is dense and occasionally telegraphic, but nothing is redundant.

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 three-parameter schema-browsing tool with an output schema, annotations, and authentication notes, the agent has enough to call it correctly and to know what to do with the results. The only real gap is the absence of any hint about pagination or directory size limits, which is a modest omission given the declared closed-world scope.

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 67%, and the description compensates by explaining that index_ref must be omitted for the root, that each scope returns topic index_ref links usable directly, that references must be copied unchanged, and that references are bound to a single schema name/version. It also cues collection of schema_ref values for a follow-up call. It adds real navigational meaning beyond the schema's terse parameter docs.

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 states the tool is for discovering unfamiliar fields and describes browsing a root directory, per-scope topic index_ref links, and following references to nested records, dictionary values and variants. Combined with the title this pins down the verb and resource clearly, and it implicitly separates the tool from get_planning_schema_definition by assigning that sibling the 'read the actual definition' role. The opening sentence is a little oblique about return shape, but scope is unmistakable.

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 explicit operational rules: omit index_ref for the root, skip opening a scope when a topic link is already present, collect schema_ref values across topics and then batch-read them with get_planning_schema_definition, and reuse cached directories at the same name/version. It also names exclusions — do not explore unrelated topics and do not read schema before every save — and clarifies that priority order is interview order, not requiredness. This is when-to-use, when-not, and named-alternative guidance in one place.

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