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

With no annotations, the description carries the full burden. It does disclose two important traits: the tool is paid ($0.01 USDC on Base, corroborated by the paymentSignature parameter) and its output reflects drawdown auto-lock status. It does not say whether the call is read-only/pure computation, what happens when no payment signature is supplied, or how errors surface.

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?

A single dense sentence with the core operation front-loaded and no filler. It compresses several concepts into one line, which borders on over-packing but nothing is wasted.

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 an 8-parameter, no-annotation, no-output-schema tool, the description covers the domain and the payment requirement but leaves return content (lot size units, lock-status format) and two parameter meanings unstated. Adequate to start, not sufficient to call confidently.

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 75%, so the schema documents most parameters and the baseline is 3. The description adds conceptual context (spread/commission friction, drawdown limits) but does not clarify the two undocumented drawdown-limit parameters or how riskPercent and currentEquityUsd interact with accountBalanceUsd.

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?

States a specific verb and resource ('Calculate exact CFD/Forex lot size') and adds differentiating qualifiers (ECN spread/commission friction, prop-firm drawdown auto-lock). An agent can tell this apart from get_cfd_microstructure or get_ict_sessions. It does not name siblings, but the operation is distinct enough.

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?

No statement of when to use this tool versus alternatives, no prerequisites (e.g. must have account balance and stop distance), and no exclusions. The prop-firm framing implies a use case but the agent must infer it. There is also no guidance that this call costs $0.01 USDC.

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