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

Annotations already declare readOnly=false, idempotent=false, and destructive=true. The description adds meaningful context beyond those: internal notes stay inside Linnworks while external notes may reach the sales channel, and it clarifies that each call appends a new note rather than updating one. It does not explain permission requirements or why destructiveHint is true, keeping it from a 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?

One tightly packed sentence front-loads the WRITE nature, then covers scope, note visibility, idempotency behavior, and the HTTP endpoint without any 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?

For a simple three-parameter write tool with full schema coverage, annotations covering safety, and no output schema, the description supplies everything an agent needs: purpose, scope, side effects, idempotency, and endpoint. No critical behavioral detail is missing.

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 schema documents all three parameters including the order_id UUID pattern and note length limits. The description adds semantic meaning for the 'internal' parameter by explaining that internal notes are visible only inside Linnworks while external notes may be passed to the sales channel.

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 and resource ('add a note to an order') with scope ('open or processed') and distinguishes itself from the sibling retrieval tool get_order_notes. An agent can identify the operation without opening the 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?

Provides clear context for when the tool applies (open or processed orders) and explains the internal vs external note distinction, but does not name alternatives or state when not to use it. No sibling add-note alternative exists, so routing guidance is not needed.

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