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

The annotations already declare destructiveHint=true, idempotentHint=true, and openWorldHint=true, so the description is not required to carry the safety profile. It adds the merge-semantics context, but says nothing about what makes the operation destructive (e.g., renaming side effects on references) or auth requirements, which is the extra context that would earn a 4–5.

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?

A single sentence, front-loaded with the action and the affected fields, with the omitted-field behavior as a trailing qualifier. No wasted words.

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?

An output schema and annotations reduce the burden, but the description omits the ledger-target concept and any consequence of the destructive rename/privacy change. Adequate for a simple patch tool, 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 coverage is 75%, so the schema largely documents parameters (including the 'private' public/private semantics and name pattern). The description mirrors three of the four fields but never mentions the `ledger` target parameter (owner/name), which is the key addressing input for an unpinned credential.

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 ('Change') and resource ('a ledger') plus the exact mutable fields (name, description, privacy), which clearly separates it from createLedger, deleteLedger, and deleteLedgerFiles. It stops short of naming any sibling explicitly, so 5 isn't warranted.

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?

'Omitted fields stay as they are' gives useful partial-update semantics, implying this is a merge/patch operation rather than a full replace. However, there is no guidance on when to use this versus siblings such as createLedger or on any prerequisites (permissions, whether a ledger must already exist).

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