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

readOnlyHint=true already tells the agent this is a safe read, so the burden is lower. The description adds the upstream endpoint (GET /coupons), which mildly corroborates read semantics, but says nothing about pagination behavior, default page size, or whether archived coupons are hidden by default.

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?

Two short, front-loaded sentences with no padding. The endpoint reference is mildly redundant but costs little and confirms the underlying operation.

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 read-only list tool with fully documented parameters there is no output schema to explain, and the annotations cover the safety profile. However, nothing in the description addresses pagination mechanics (cursor/next page) or that coupons may be archived and hidden, which is the main behavioral nuance of this tool.

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%, with limit, cursor, and show_archived each documented, including the 1–100 range and the origin of the cursor. The description adds no parameter detail beyond that, 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?

States a specific verb+resource ('List coupons in the Orb account'), which cleanly separates it from the other list_* siblings (customers, invoices, plans, prices, subscriptions) by resource. It stops short of naming any alternative or scope constraint, so it is clear but not maximally distinguishing.

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?

There is no guidance on when to use this tool versus alternatives, no prerequisites, and no mention of how pagination or the archived flag should be used. Usage is only implied by the word 'List'.

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