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

Annotations already declare idempotentHint=true, destructiveHint=true, openWorldHint=true, and readOnlyHint=false. The description adds context beyond that by noting the invocation is 'paid' and that settlement authority must come from the host boundary, but it does not explain what gets destroyed, what authorization is required beyond that condition, or how replay behaves in detail.

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?

The description is two tightly written sentences with no wasteful repetition. The purpose is front-loaded, followed immediately by the admission scope, making it efficient for an agent to parse.

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 complex tool with 9 parameters, nested objects, no input schema descriptions, and a mutation/destructive profile, the description covers only purpose and offer scope. The output schema helps with return values, but the input contract is left almost entirely unexplained, so an agent lacks enough detail to invoke the tool correctly.

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 schema has 9 parameters with 0% description coverage, and the description mentions none of them by name or meaning. While terms like 'idempotent' and 'offer' loosely relate to idempotency_key and offer_id, no parameter-level semantics are communicated, so the description fails to compensate for the schema gap.

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 states a specific verb pair ('Admit or replay') and resource ('Browser Session invocation'), and scopes it to 'browser.session offer' envelopes. It distinguishes the tool from generic invocation siblings by restricting admission to that offer, though it does not explicitly name an alternative tool.

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?

It gives a precondition ('when settlement authority is supplied by the host boundary') and an exclusivity rule ('Only envelopes for the browser.session offer are admitted'). However, it does not say when to use this instead of siblings like ausca_prepare_invocation or ausca_browser_session_connect, so usage remains implied rather than explicit.

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