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

Annotations already declare destructive=true, idempotent=false, openWorld=true, readOnly=false, so the safety profile is covered. The description adds genuinely new behavior: WAPI status resolution, conditional FixedOrderLine usage for CompletedAutoOrderPending, the confirmation gate, and internal resolution of the channel header. It stops short of saying what state change is irreversible or what a second call does.

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?

Three sentences, purpose first, then routing behavior, then prerequisites — well front-loaded and free of filler. It is dense with internal jargon (WAPI, FixedOrderLine, CompletedAutoOrderPending, HGRApi Header channel) that a first-time agent may not decode, which slightly undercuts clarity.

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?

With an output schema, full param coverage and rich annotations, the description need not explain return values, and it does cover the preconditions and internal resolution steps. The main residual gap is a one-line warning about the destructive, non-idempotent consequences of marking lines purchased.

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 all three parameters are documented structurally; this sets the baseline at 3. The description reinforces the confirmed gate and notes channelOAuthId/auth headers are resolved internally, but adds no format or value-level detail beyond the schema.

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+scope: 'Marks exact order lines as purchased in HGR.' The 'exact' qualifier and the note that FixedOrderLine is used only for CompletedAutoOrderPending give partial differentiation from the sibling hgr_mark_order_lines_fixed, but the sibling is never 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 gating condition ('requires confirmed=true after showing the full HGRWeb warning') and the status-routing note imply when this path applies, and the schema's confirmed description adds a 'do not use unless already purchased' exclusion. However, the description never explicitly names which sibling to use instead (process_order_lines, mark_order_lines_fixed, force_process_order_lines), leaving the agent to infer the boundary.

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