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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is covered. The description adds the permission tiers but does not explain what makes it 'destructive' (e.g., permission escalation or revoking access on downgrade) or the credentials required. A 3 is warranted with annotations carrying the disclosure burden.

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 front-loaded sentence with zero waste that captures both the add and update behaviors. Appropriately sized for the tool's scope.

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 exists so return values needn't be explained, and annotations cover safety. However, for a destructive mutation the description omits what happens to an existing collaborator, whether lowering permission revokes access, and the unpinned-ledger defaulting behavior mentioned in the schema.

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 67%; the ledger and permission parameters are described in the schema, including the read/write/admin enum and the default behavior. The description repeats the permission values without adding syntax, format, or default details, and 'collaborator' format is undocumented in both. Baseline 3 fits where the schema does most of the work.

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 states a specific verb (add/update) and resource (ledger collaborator), and the 'add or update' framing communicates the upsert nature. It is distinguishable from removeLedgerCollaborator by implication, though no sibling is named explicitly.

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 'add ... or change an existing ... permission' wording implies when this is used, but it never names the alternative (removeLedgerCollaborator) or states when-not to use it. No prerequisites or conditions are given.

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