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

Annotations declare only readOnlyHint=false, so the description must carry the rest — it does add that a paid session is required, which is real context beyond structured fields. But it omits whether the session is consumed, whether the repair is idempotent, whether the original CSV is altered, and whether the repaired text is returned or written.

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 no filler; the prerequisite is stated compactly. It is efficient, though so terse that no space is given to the operational details described above.

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 mutation tool with a paid-prerequisite flow, 2 required parameters, an undocumented optional parameter, and no output schema, the description is too thin. It should indicate what the result is (repaired CSV text vs. a status) and what filename does; neither is covered.

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 33%: only checkout_session_id is documented in the schema. The description adds nothing about csv_text (size limit 250000), filename (optional, purpose unstated), or the interaction between the two required parameters — the mandatory fields are left entirely to inference.

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 ('Repair one CSV'), which distinguishes it from repair_ics/repair_srt and from the diagnose_* siblings by file format. It does not say what 'repair' actually does to the CSV, so the purpose is clear at the routing level but not operationally.

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?

'Using a paid ReadyKit Checkout Session' implies a prerequisite (a checkout must be completed first), and 'one CSV' implies single-file scope per call. However, it never says when to choose repair_csv over diagnose_csv, nor what happens if the CSV is healthy — guidance is only hinted at.

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