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

Annotations already declare non-read-only, non-destructive, open-world behavior, and the description adds real context beyond them: the option notifies no one and stays local until send_estimate, removal must be done in the Hoousecall Pro UI (no tool exposes it), it fires without a confirmation step, and it needs a Cotlet API key with access to this app. That is meaningful side-effect and auth disclosure for a mutation 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?

The core purpose is front-loaded, but the text drifts into tangential material: the UI three-dot-menu removal instructions and the dangling 'runs without asking first for that reason.' The sentences are slightly awkward and not tightly ordered, though nothing is egregiously wasteful.

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 output schema, the description covers purpose, downstream effect (nothing is sent until send_estimate), the draft-estimate precondition, and the API-key requirement. The only real gap is the shape of the return value, which is minor given the absence of an output 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 description coverage is 100%, so estimate_id, name and line_items are already documented in the schema, including the price_book_id / unit_price rule. The description adds only the general idea of 'own line items and total' and does not extend parameter meaning beyond structured fields, so the 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?

The description names a specific verb and resource ('Add a named option with its own line items to a draft estimate') and reinforces it with the UI analogue '+ New option on the Estimate details page.' It clearly distinguishes the tool from sibling operations like send_estimate and create_estimate, so an agent can place it precisely.

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 establishes context — the option lives on a draft estimate and only reaches the customer when send_estimate runs — which tells the agent when this step belongs in a flow. It stops short of a crisp when-to-use/when-not statement or naming alternative tools, but for a narrowly-scoped option-adding tool the guidance is clear.

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