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

Beyond the destructiveHint/idempotentHint annotations, it discloses the concrete effect (total limit becomes the approved total), the explicitly preserved state (permissions unchanged, stopped work stays stopped), and the refusal semantics for already-applied proposals — which meaningfully nuances the idempotent hint. This is the kind of mutation detail an agent needs before committing credits.

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?

Three dense sentences with no filler: effect first, invariants second, refusal conditions third. Front-loaded and every clause carries operational information.

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?

An output schema exists and annotations cover the safety profile, so the description only needs to cover invocation preconditions and effects — which it largely does. The one remaining gap is the unexplained request_key, which an agent must guess how to populate.

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 0%, so the description must carry both parameters. It adds real meaning for proposal_id (approval state, staleness, ownership, single-use) but never mentions request_key at all, leaving its role — presumably a caller-generated idempotency/retry key — undocumented in both schema and prose.

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 first sentence gives a precise verb (apply), resource (creator-approved spending-limit proposal), and scope ('to its work, once'), and immediately clarifies what changes (total credit limit) versus what does not (video, publishing, attempt, resource permissions). An agent can distinguish this from prepare_work_budget and manage_budget without opening either 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?

The description enumerates the exact preconditions under which the call is valid and the cases in which it is refused (not approved, stale, wrong connection/work, already applied), which effectively tells the agent when this tool applies versus when not to call it. It stops short of explicitly naming prepare_work_budget as the source of the proposal_id, leaving that inference to the sibling name.

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