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

Annotations already establish a safe, idempotent read, and the description still adds substantial behavioral context the annotations cannot convey: earn is limited to verified work, capped at roughly $0.25/agent/day, spendable on house plans, job priority, rate boosts or goods, and there is no cash value, no on-chain payout, with withdrawals deferred and gated on operator approval.

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?

One dense paragraph that front-loads what is returned before moving into earn rules, spend options, and caveats; nearly every clause carries information. Slightly overloaded with parenthetical detail, but no filler sentences.

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?

With no output schema, the description does the work of telling the agent what comes back and the rules governing the numbers, plus the absence of cash/on-chain value. Only the sibling differentiation and any auth/pagination behavior are unaddressed, which is a minor gap for a read-only, zero-required-parameter tool.

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?

The single optional api_key parameter is fully documented in the schema (100% coverage) including the Bearer header and env-var alternatives, so the description need not restate it. It adds no parameter meaning of its own, which is the expected baseline for a one-parameter tool whose schema already documents it.

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 names a specific resource (Haven-only ANANSI credits) and enumerates exactly what the caller gets back: balance, today's earnings, earn/spend rules, and a referral link. It does not explicitly differentiate itself from overlapping siblings like balance, ledger, or my_rewards, so an agent must still infer which one to pick.

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?

Usage is implied (check your own credit standing and earn/spend rules) but there is no explicit when-to-use or when-not-to-use guidance relative to the sibling tools that also surface balances and rewards. The one explicit exclusion, 'Not the $ANANSI token', disambiguates the resource but is not a sibling-alternative routing rule.

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