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

With no annotations, the description carries the full burden and does well: it discloses that this is a creation-style mutation, that the copy is re-encrypted (a security-relevant trait), that a new id is assigned, and how agent access is resolved via owner+privacy rules. It omits error behavior (e.g., nonexistent id) and how the new id is surfaced to the caller.

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 tight sentences that front-load the auth requirement and the core clone action, then add only useful detail (what is copied, naming, access). No filler.

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 3-param mutation tool with no annotations and no output schema, the definition covers auth, payload of the copy, naming, and access propagation. Gaps are minor: it doesn't describe failure modes or how the new session id is returned.

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%, so the id, label default, and privacy enum are already fully documented in the schema, including the same "<source> (копия)" default and the -1/1/2 privacy mapping. The description adds only the oblique "owner+privacy rules" note, so baseline 3 applies.

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?

States a specific verb (clone/copy) and resource (vault session), and spells out exactly what is copied (cookies, fingerprint, storage, urls). This naturally distinguishes it from vault-create-session: it duplicates an existing session rather than making a fresh one.

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 "[Auth Required]" prefix and the fact that it operates on an existing session imply the correct context, and the copy semantics distinguish it from vault-create-session. However, it never explicitly states when to prefer cloning over creating, nor any exclusions.

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