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

Goes well beyond the annotations by disclosing a non-obvious side effect: changing valid_until or reminder_offsets cancels pending reminders and reschedules them. It also explains the two-step confirmation protocol (status='confirmation_required' with action_id and plan_token, write only after confirm_action), which is critical context for a destructiveHint=true tool and is not derivable from the schema or annotations.

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?

Well front-loaded: purpose, then editable fields, then side effects, then scope, then the confirmation protocol. The capitalization for EMPHASIS (RENEWAL, CANCELS, CONFIRMATION, PROPOSED) is slightly noisy, but the field list and side-effect sentences each carry information an agent needs.

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 10-parameter destructive mutation with no output schema, the definition covers the essentials: ownership scoping, side effects, and the confirmation handshake. The one remaining gap is partial-update semantics (whether omitted fields are preserved), but the field list plus required id make the intended call pattern clear enough to invoke correctly.

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?

With 0% schema description coverage, the description carries the load and largely succeeds: it names nine of the ten parameters and adds real meaning such as number_masked being ≤4 chars and reminder_offsets driving rescheduling. However, document_id (integer|string|null) is listed without explaining what it references, notes has no semantics, and the enum values for kind are left entirely to 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 and resource ("Update one of the caller's tracked documents by id") plus the scope ("the RENEWAL flow"), which distinguishes it from add_tracked_document, delete_tracked_document, and get_tracked_document. The enumeration of editable fields makes the mutation surface explicit up front.

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 description makes clear this is for modifying an existing tracked document owned by the caller and ties it to the renewal workflow, and it correctly routes the agent to confirm_action for the actual write. It does not state exclusions, e.g. that add_tracked_document should be used for new documents or that only the listed fields can be changed via this path, so it falls short of explicit when-not guidance.

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