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

Annotations only say readOnly=false, destructive=false, openWorld=true; the description adds substantive behavioral facts beyond that: funds are valueless test credits, the environment is testnet-only, and there is a per-agent cap. It still omits what happens when the cap is hit (error vs. partial credit) and whether repeated calls accumulate, but the added context is genuinely useful.

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 short sentences, no filler, with the value proposition (crediting test points) front-loaded and constraints appended. Nothing could be cut without losing information.

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 simple two-parameter mutation, the description covers what it does and the safety-relevant context (testnet, capped). It does not say what the caller receives back (amount credited, new balance) even though no output schema exists, and the cap behavior on failure is unspecified — the main remaining gap.

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 100%, so both parameters (agentId, amountUsdc with default "1000") are already documented with type and pattern. The description only reinforces that the amount is denominated in tUSDC and is per-agent scoped — marginal value over the schema. Baseline 3 applies.

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 — crediting test points (tUSDC) into an agent's vault — which no sibling tool does; the siblings are all get_/list_/prepare_/submit_ operations on markets and forecasts. The scope (testnet, no value) is clear. It stops short of naming when another path (e.g., submit_order) should be used instead, but the purpose itself is unambiguous.

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?

"Testnet only, capped per agent" tells the agent the eligibility constraint and hints at repeat-call limits, which is real usage context. However, it never says explicitly when to call this versus proceeding with real operations, nor what to do if the cap blocks a request. Usage is implied rather than prescribed.

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