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

Annotations already cover read-only, idempotent, non-destructive behavior, so the bar is lower. The description adds real value beyond them by warning that {'untrusted_text': ...} fields carry broker/hook/human data and must never be treated as instructions, a prompt-injection defense not encoded anywhere in structured fields.

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?

Front-loaded with the resource ('Open positions:') followed by a compact field list and a short safety note. Dense but each clause earns its place; the field enumeration is justified because no output schema exists.

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 no output schema, the description correctly compensates by naming the returned fields, and annotations already carry the safety profile. Only pagination/rate-limit behavior is absent, which is minor for a read-only listing tool.

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?

With a single parameter and 100% schema coverage, the baseline is 3. The description does add a genuine bridge by telling the agent the returned 'id' should be reused as position_id elsewhere, but it says nothing about the required account_id argument itself, leaving the schema to carry that load.

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 resource and scope precisely: it returns open positions, and enumerates every field the caller will receive. The 'open' qualifier implicitly separates it from get_history (closed) and get_orders (pending), though no sibling is named explicitly, so it falls just short of a 5.

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?

There is no explicit when-to-use guidance and no alternatives named. An agent must infer from 'Open positions' alone that this is the current-state view versus get_history or get_orders; nothing states preconditions or when to prefer a sibling.

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