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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the safety profile is covered structurally. The description adds nothing beyond that — no statement of what a registration does, whether it requires prior identity verification, or what a re-register of an existing session_id returns. It does not contradict the annotations, but it contributes zero behavioral context.

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?

Extremely short, but short due to under-specification rather than efficiency. The line is also marred by a character-encoding artifact ("—"), and its leading bracketed tag conveys no actionable 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?

The tool is simple (one required string parameter, no output schema), so it does not need volume — but it still needs to say what registering a session produces and how it relates to ratchet_advance. With no output schema and no description of effects, an agent cannot predict the result of calling it.

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 0% for the single parameter; only a bare example ("sess-001") is present. The description does not explain the origin, format, or lifecycle of session_id (client-generated? returned by another call?), so it fails to compensate for the coverage 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 is a bracketed tag plus a restatement of the title: "[identity] RatchetGate — register session". It names a resource (session) and a loose verb (register), but never says what registering a session accomplishes or what state it creates. It also gives no way to distinguish this from siblings like ratchet_advance, agents_register, or sla_register.

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 to call this versus any of the ~48 sibling tools, no prerequisites, and no ordering hint (e.g., relative to ratchet_advance). The agent must guess entirely from the name.

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