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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds substantive domain behavior: the fee is shared equally among arbitrators, the 1.5 billion rial cap, and the 5–30 million rial range for non-financial claims. No error/edge behavior is described, hence not a 5.

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 dense sentence that is front-loaded with the purpose and the governing bylaw, and every clause (bands, cap, sharing rule, non-financial handling) carries weight. It would read more easily if split, but there is no wasted text.

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?

No output schema exists, yet the description fully specifies the fee logic an agent needs to interpret the result. The one residual ambiguity is the rial cap versus the Toman-denominated claim_toman input, which is disclosed but not reconciled, keeping it from a 5.

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 100% (baseline 3), but the description goes further by explaining how the fee relates to parameters — the marginal bands apply to the claim amount, the result is shared equally among arbitrators, and non-financial claims use a flat per-arbitrator range. This adds real meaning to both claim_toman and arbitrators.

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 (calculate حق‌الزحمهٔ داوری), anchors it to a named bylaw (approved 1401/06/05) and outlines the exact computation bands and cap. An agent can distinguish this fee from calculate_lawyer_fee, calculate_diyeh and the other calculate_* siblings without opening any schema.

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?

Gives a concrete applicability condition — it applies when the arbitrator and the parties have not agreed a fee — which tells the agent the statutory-default scenario. It does not name alternatives or an explicit when-not-to-use, so it stops short of a 5.

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