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

Annotations declare this is a non-readOnly, non-idempotent mutation, and the description goes well beyond them: it discloses which balances actually move (settled, 30-day-old top-ups and peer-granted credit), that credit is never paid out and loans carry no Kula Labs guarantee, the 5% commons skim and its default override, and that a key is required. This is exactly the behavioral context an agent needs before a mutating call.

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 opening sentence is a dense run-on enumerating all six modes, which is slightly cluttered, but the following sentences each carry distinct, useful information (credit movement rules, commons mechanics, access requirement). Little is wasted and the mode list is front-loaded.

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 six-parameter, six-mode mutation tool with no output schema, it covers the mode behaviors, the settlement rule limiting which credit moves, the commons tax, and what status returns (circle, sponsor code, earnings). It leaves some gaps around amount limits and error/failure behavior, but the critical semantics are present.

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 67%, and the description adds real meaning where the schema is thin: it explains commons_pct (5% default, what the commons funds), the loan/post/award/take_back target semantics, and the due_days default of 30 reflected in behavior. It does not clarify amount_chf bounds or units, which the schema leaves undocumented.

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 description uses specific verbs (give, lend, repay, award, take back, see) tied to a concrete resource (credit, board post, loan, question/answer) and enumerates the modes the tool supports. It clearly separates this from generic write tools like agents_post or leave_gift, though it never names a sibling explicitly to route between them.

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?

It effectively maps each mode to its use case ('give or lend credit to the author of a board post', 'repay a loan', 'award the reward on your question', 'see your circle... mode status'), which is real when-to-use guidance for a multi-mode tool. It stops short of stating when NOT to use it or which sibling to prefer for adjacent tasks.

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