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

Annotations only declare readOnlyHint=false, so the description must add the rest. It usefully discloses that the operation is gated on a paid Stripe session (a cost/precondition signal), but says nothing about whether the original file is modified, what happens on an invalid or unpaid session, or what a successful repair returns.

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?

A single, front-loaded sentence with zero filler. It is efficiently sized, though the brevity edges into under-specification rather than crispness.

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 mutating, payment-gated tool with no output schema and an optional filename parameter, the description omits the essential contracts: input format expectations, what the repair produces, and error behavior on bad sessions. An agent would have to guess before invoking.

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 coverage is only 33%: checkout_session_id is documented, but calendar_text has no description (only a 250k maxLength) and filename is entirely bare. The description does not compensate—it never explains what calendar_text should contain, what filename controls, or the size constraint, leaving two of three parameters under-specified.

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 (repair) and resource (one ICS file), which distinguishes it cleanly from repair_csv and repair_srt. What 'repair' actually means for the calendar content is left implicit, but the resource scope is unambiguous.

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 phrase 'using a paid ReadyKit Checkout Session' implies a prerequisite (a completed payment) but never states when to call repair_ics versus diagnose_ics first, or what to do if checkout is unpaid. Usage is only indirectly implied.

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