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

With no annotations provided, the description carries the behavioral burden. It discloses the key side effects: the server freezes the manifest's canonical sha256 commitment and the attempt must be closed by completion or evidenced abort. It does not describe response shape or permission requirements, but the core mutation and lifecycle behavior is transparent.

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 short sentences with no filler. The most important constraint is front-loaded ('BEFORE reader spend'), and each sentence earns its place: purpose, manifest exactness and freezing, and lifecycle obligation.

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?

This is a mutating, multi-parameter tool with no annotations and no output schema. The description covers the core workflow but leaves gaps: it does not say what is returned (e.g., attempt ID or commitment reference), how to use that result with submit_measurement or abort_attempt, or whether preflight_attempt should be run first. Adequate but not complete.

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%, and the schema already explains each parameter, including that the manifest must match the later submit_measurement filing. The description's 'supply the exact manifest object you will later file' largely restates the schema's manifest field, so it adds little beyond the baseline.

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 names the exact operation ('preregister one measurement attempt') and the key temporal condition ('BEFORE reader spend'). It also distinguishes this from related siblings like submit_measurement and abort_attempt by noting that the manifest is filed later and the attempt must eventually be closed.

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 clearly states when to use the tool: before reader spend, with the exact manifest that will later be filed, and with the obligation to close the attempt via completion or evidenced abort. However, it does not explicitly name alternatives such as preflight_attempt or say when not to use this tool, so it stops short of full exclusion guidance.

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