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

Annotations already declare mutation + idempotency, and the description adds substantial context beyond them: no-op semantics on repeat calls (granted: false, still returns a readable balance, never a double grant), that no x402 facilitator is needed, and that no payment is required. This is exactly the kind of behavioral detail the schema and annotations cannot carry.

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?

Front-loads the key promise (FREE first-run) before details, and every clause is on-topic. The embedded four-step recipe is useful but stretches the definition; slightly tighter phrasing would keep it at a 5.

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?

An output schema exists, so return format needn't be documented, yet the description still explains the meaningful granted: false case. Combined with the idempotency and no-payment caveats, an agent has everything needed to call 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 coverage is 0%, so the description must compensate. It identifies the single param as a Base address (payer, 0x + 40 hex), adding chain context beyond the raw pattern. It could still say what happens with a malformed or non-Base address, so it stops short of a 5.

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 (grant) and resource (free taste / entry-tier credits) with exact scope (3 questions, 1000 credits each) and names the mechanism (credit rail, no x402). It is unmistakably distinct from siblings like tollbridge_get_decision or tollbridge_decision.

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 an explicit first-run recipe with ordered alternatives: tollbridge_scout → read balance via credit ledger → tollbridge_get_decision/get_resolution → tollbridge_decision only when the latest sentence is terminal. Both the when-to-use and the sequencing of downstream siblings are spelled out.

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