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

Annotations already flag destructiveHint=true and non-idempotent, but the description adds far more: REAL MONEY, a market order from the user's agent wallet, the required api:trade scope, and the specific failure modes (409 naming a mismatched field, 410 for expired proposals, 409 with price_drift for a moved market). This is materially beyond what structured fields convey.

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 action, then the money/safety warning, then the parameter rules and error behavior. Dense but every clause carries operational information; no filler or restated title language.

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 destructive, non-idempotent real-money tool the description covers preconditions, scope, integrity checks and error codes thoroughly. The only gap is the success side — no hint about what comes back (order id, fill status), which matters somewhat since there is no output schema, though error handling is what an agent most needs here.

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 only 60% and the schema only says 'REQUIRED for execute — echo confirm_echo.X'; the description explains the integrity-check mechanism, that the echo must match the proposal exactly, that mismatches 409 naming the field, and that cancel needs none of these fields. That is real semantic value over the schema.

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 pair (execute/cancel) applied to a specific resource ('a previously proposed trade'), which cleanly separates it from propose_trade and propose_stock_order/confirm_stock_order in the sibling list. An agent knows exactly what this tool does without opening the schema.

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?

Gives explicit when-to-use ('after a human approves a proposal'), explicit when-not ('NEVER call confirm_trade autonomously, and NEVER chain it automatically after propose_trade'), and a hard precondition (present the full preview and obtain explicit approval). The decision=cancel branch is also distinguished ('needs no echo fields').

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