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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description doesn't need to restate safety. It adds valuable behavioral context beyond structured data: the status vocabulary (awaiting_funds, standing, bumped, missed, refunded, cancelled), the 'exact amount still to pay', the placement id condition, and the Authorization: Bearer JWT requirement.

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 that front-loads the core purpose ('Every bid the caller has placed, newest first') and efficiently packs in status meanings, amount due, placement id condition, and auth requirement. Every clause earns its place with zero 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 zero-parameter, read-only listing tool with no output schema, the description fully covers what the caller will receive (status, amount due, placement id), ordering, and authentication. Nothing essential is missing for correct invocation and interpretation.

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?

The input schema is empty (0 parameters), so there are no parameter semantics to document. Baseline 4 applies, and the description correctly focuses on output behavior instead of parameters.

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 opens with 'Every bid the caller has placed, newest first' – a specific, scoped read operation on the caller's own bids. It enumerates returned fields (status, amount, placement id) and distinguishes itself from siblings like adspace_bid (placing a bid) and adspace_bid_cancel (cancellation).

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?

Clear context is provided: this is for viewing the caller's own bids, with explicit scoping ('caller has placed') and ordering ('newest first'). It doesn't explicitly name alternative tools or state when not to use it, but the sibling list makes the differentiation obvious.

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