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

Annotations already cover readOnly/idempotent/openWorld, and the description adds genuinely new behavioral context: evidence reads require a website account on the public endpoint while the internal API-key endpoint reads it directly, no passport or student category is assumed, and the public endpoint returns English natural-language text preserving sources, conditions and pagination. That auth and output-format disclosure goes meaningfully beyond the annotations.

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 purpose is front-loaded in the first sentence, and each subsequent sentence addresses a distinct concern (evidence flag, auth, defaults, locale, output format). It is dense and slightly repetitive in restating includeEvidence's default, but nearly every sentence 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?

With 5 parameters, no output schema, and 80% schema coverage, the description supplies the missing context an agent needs: auth requirements for evidence, the absence of default assumptions, locale behavior, and the shape of the response (English natural-language text with sources and pagination). Only explicit sibling routing is missing.

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 80%, so the schema already documents most parameters well. The description adds some value by stating that no passport or student category is assumed (relevant to the defaultless passportCountry and studentType) and that locale selects website links, but it adds little syntax or selection logic beyond the schema. Baseline 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 opens with a specific verb and resource ('Read school facts') and enumerates the returned domains: processing priority, campuses, dates and linked RTO. It clearly distinguishes the tool from a generic lookup, though it never explicitly contrasts itself with close siblings like get_school_campuses or get_rto, which also surface overlapping data.

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 rather than stated: includeEvidence defaults to false, and the account/API-key conditions are described. But there is no explicit when-to-use-this-vs-alternative guidance against the many sibling tools (get_rto, get_school_campuses, search_rtos), leaving the agent to infer routing.

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