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

Beyond the readOnly/idempotent annotations, the description discloses a lot: entitlement gating on the vertical, the exact truncation rule (first 5 rows in full plus locked.count/locked.by_type for lists, first 3 related names for records), fields never returned (contact values, decision-maker names), and the entitlement/locked response fields that report withheld data.

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?

Content is front-loaded — what the tool returns comes first, access/entitlement last — and every sentence carries information. The first sentence is a dense run-on listing many returned elements, which slightly hurts readability but does not waste space.

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 no-output-schema, single-param tool, the description covers returned contents, id provenance, and access restrictions thoroughly. It stops short of relating this tool to the closest sibling (get_borrower_facilities), leaving a small gap in routing context.

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 single dfx_id parameter is already documented with its provenance in the schema. The description adds no format or validation detail beyond what the schema provides, so the 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?

The description states a specific resource (one facility = one borrower group in one instrument class) and enumerates exactly what comes back: size, pricing, maturity, lender group, history, and changes at facility grain. It is clearly distinguishable from list-style siblings, though it never names a sibling directly (e.g. get_borrower_facilities) for contrast.

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 tells the agent where the required dfx_id comes from (get_borrower_capital_structure, search_credit_maturities, or an event), which is genuine usage guidance. However, there is no explicit when-to-use/when-not-to-use versus other facility or capital-structure tools, so usage remains largely implied.

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