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

With no annotations, the description carries the full behavioral burden and does disclose one meaningful trait: the stake is returned, making this a non-destructive reversal. However, it says nothing about authorization requirements (the schema notes the key scope must allow 'backed-bids'), idempotency, or what happens if the bid is no longer competing.

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 front-loaded sentence pairing the action with its key precondition and side effect; every clause earns its place with no filler.

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 one-required-parameter mutation with full schema coverage and no output schema, the description covers the action, the eligibility window, and the stake-return outcome. The main residual gap is failure behavior when the precondition no longer holds.

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%, so both parameters (backing_id and the deprecated api_key fallback with its header guidance) are already fully documented in the schema. The description adds no parameter-level detail beyond what is structured, 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?

States a specific verb (withdraw) and resource (a backing), plus the precondition that the bid is still competing, which separates it from backed_bids_back and backed_bids_mine. It does not explicitly disambiguate from the similarly named sibling bids_withdraw, so the resource distinction is left to inference.

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?

The phrase 'while the bid is still competing' implies a usage window and implicitly a when-not condition (once the bid is settled/lost the withdrawal is no longer valid), but no alternative tool is named and no explicit exclusion or error path is given.

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