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

Annotations already declare readOnlyHint=false, destructiveHint=false, and idempotentHint=false, so the safety profile is partly covered. The description adds only 'Costs are priced at it,' which vaguely hints at downstream pricing effects but does not explain overwrite behavior, effective-date semantics, or permission requirements.

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?

The definition is a single sentence with no wasted words, but it is not front-loaded with the core action. The opening phrase 'What the company pays a coding tool from a day' is confusing and delays the actual field list.

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?

This is an eight-parameter write tool with zero schema description coverage. The description fails to compensate: it does not explain parameter meanings, usage conditions, or the effect of setting a contract, leaving the agent without enough information to invoke it 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?

Schema description coverage is 0%, so the description must carry parameter meaning. It lists six of eight field names (plan, seat_usd, seats, unit_usd, discount_pct, included_usd) but does not explain their semantics—e.g., the distinction between seat_usd and unit_usd, or what included_usd means. It does clarify valid_from as a YYYY-MM-DD date, but tool is never described.

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?

The title 'Set a tool's contract' gives a clear verb+resource, but the description is cryptic: 'What the company pays a coding tool from a day' reads as a definition rather than an action. It lists fields but never states that the tool creates or updates a contract record, and it does not differentiate from sibling tools like set_price.

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 such as set_price, plan_costs, or seats. No prerequisites or exclusions are mentioned, leaving the agent to infer usage context from the name alone.

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