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

Annotations supply only destructiveHint=false, so the description carries the real behavioral burden and does: it discloses the proposal-only, no-side-effects-until-confirm_action semantics, the vesting gate, the quantity cap, the tax-scheme carryover, and the unlock_shareflo dependency. These are exactly the operational traits an agent needs before calling a mutation-adjacent tool.

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?

Four sentences, each carrying distinct load: the action, the outcome, the preconditions, and the confirm gate. The most decision-relevant constraint (proposal-only) and the dependency chain are front-loaded rather than buried.

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 5-parameter tool with no output schema, the description covers preconditions, side effects, and correction semantics thoroughly. The one small gap is that it never says what the call returns (e.g., a proposal UID) even though replaces_proposal_uid presupposes the agent can obtain an open proposal's UID.

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 holding_uid, quantity, exercise_date, notes, and replaces_proposal_uid are already documented in the schema. The description restates the vested-quantity constraint but adds no syntax, format, or edge-case detail beyond what the schema provides, making the baseline 3 appropriate.

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 opening sentence names a specific verb (proposes exercising) and resource (options from one option holding), and the follow-up explains the resulting share conversion and tax treatment. An agent can distinguish this from siblings like convert_share_class or transfer_shares without opening any schema.

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?

It states explicit prerequisites and routes to alternatives by name: stop_vesting must have run first if a vesting schedule exists, unlock_shareflo must have been called, and confirm_action is required before anything takes effect. It also covers the correction path via replaces_proposal_uid, leaving no when-to-use ambiguity.

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