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

With no annotations, the description carries the full burden of disclosing behavior, but it only states the core mathematical operation. It does not explain how the array is provided (the schema has zero parameters), what the output format is, how edge cases like empty arrays or NaN values are handled, or whether the original array is modified. For a tool whose input mechanism is entirely unclear, this is a significant transparency gap.

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?

The description is short, but it opens with 'Cumulative Max:', a redundant label that merely restates the tool name before delivering the actual definition. This wastes the front-loaded position where the missing input/output details could have been placed. It is not bloated, but it is under-structured for the information an agent needs.

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 tool with no output schema and no annotations, the description must be complete on its own, and it is not. The single most important piece of information, how to supply the input array, is absent and even contradicted by the empty parameter schema. An agent cannot reliably invoke this tool based on this definition, despite the simple underlying concept.

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 description mentions an array as the input, yet the input schema declares zero parameters, so an agent cannot represent or pass that array. The description adds semantic information about the conceptual operand, but this directly conflicts with the empty schema and leaves the agent with no usable calling convention. The baseline of 4 for zero parameters is overridden because the description implies a parameter that the schema does not expose.

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 operation, cumulative maximum, on a named resource, an array, so an agent knows what computation is performed. It is not a pure tautology because it identifies the array as the operand, and the maximum orientation distinguishes it from cumulative-min and cumulative-sum siblings. However, it does not explicitly contrast it with rolling-max or find-max, so differentiation is partial.

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?

The use case is implied: call this when you need the cumulative maximum of an array. No explicit when-to-use or when-not-to-use guidance is given, nor are alternatives such as x402-cumulative-min, x402-cumulative-sum, or x402-rolling-max named. The problem statement is clear enough for a simple tool, but the description leaves selection among close siblings to the agent's inference.

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