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

No annotations are provided, so the description carries the full behavioral burden, and it discloses nothing. It does not say whether registration is idempotent, whether it creates or mutates state, what happens if the session already exists, or what auth is required.

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?

It is short and technically front-loaded, but this is under-specification rather than conciseness. The single fragment carries no actionable content, so brevity does not earn its place here.

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?

With no annotations, no output schema, 0% parameter coverage, and a one-line description, an agent has essentially nothing to reason about: no side effects, no return behavior, no failure modes, no context on what a 'session' is in this system.

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 compensate for the single session_id parameter, and it offers nothing beyond the parameter name. The only aid is the self-describing name and the 'sess-001' example in the schema, which the description does not build on (no format, source, or lifecycle meaning).

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 is essentially a restatement of the tool name: 'ratchet_register' becomes 'register session', with '[identity] RatchetGate' acting as a category tag. It does not state what registering a session accomplishes or how it differs from ratchet_advance or ratchet_probe. This is close to tautology rather than a specific verb+resource statement.

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?

There is no indication of when this tool should be used, what preconditions exist, or which sibling tool is the alternative. With ratchet_advance and ratchet_probe sitting alongside it, the absence of any routing guidance leaves the agent unable to choose correctly.

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