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

With no annotations, the description carries the full burden. It usefully discloses a real behavioral trait the schema cannot: it costs $0.01 USDC on Base via x402, so the agent knows this is a paid call. However, it says nothing about return shape, freshness/snapshot semantics, or failure modes, leaving significant gaps for a paid composite tool.

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?

Two tight sentences with the purpose front-loaded and the cost detail trailing. Every clause earns its place; nothing is padded.

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?

A six-parameter, four-required tool with no annotations and no output schema needs more than it gets. Parameter intent and the returned context bundle are undocumented, so an agent cannot confidently construct a correct call from the definition alone.

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% across 6 parameters (address, spender, token_contract, product_id, network, balance_tokens), so the description is expected to compensate and does not. The listed resources loosely hint at what is gathered but map to no specific parameter, leaving required inputs like product_id and spender unexplained.

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 clear verb (Refresh) and enumerates the specific resources aggregated: wallet, allowance, gas, price, 24h statistics, and top-of-book context. It distinguishes itself from the many narrow siblings (chain-erc20-allowance, chain-gas-state, crypto-top-of-book) by being the combined pre-trade snapshot, though it never names those alternatives explicitly.

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?

Explicitly states when to call it: 'immediately before each automated trade or payment.' That timing condition is exactly the routing signal an agent needs. It stops short of naming the narrower per-data-source siblings as fallbacks when only one metric is wanted.

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