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

No annotations are supplied, so the description carries the full behavioral burden. It does add one genuinely useful nugget that structured data does not provide – the '5 free trial calls per signed wallet' pricing and auth hint – but it says nothing about whether reveal mutates server-side state, how a board is carried between calls (the free-form 'board' string parameter), or what the response contains.

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, front-loaded with what the tool does before the pricing note. Nothing is padded, though the joined-phrase structure ('boards and reveal cells') compresses two operations into one clause in a way that slightly muddies which parameters belong to which.

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 an 11-parameter, zero-coverage, multi-operation tool with no annotations and no output schema, the description is far too thin. An agent cannot determine valid 'op' values, required parameter combinations per operation, or how state round-trips, leaving the tool effectively uncallable without trial and error.

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 11 parameters, and the description adds no meaning to any of them. The critical 'op' parameter, which presumably selects generate vs. reveal, is never explained, nor are board/row/col/rows/cols/mines/count/width/height or why they are all typed as strings. The agent has no basis for constructing a valid call.

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?

The description names a specific resource and two concrete verbs: 'Generate minesweeper boards and reveal cells.' An agent can tell this is a game board tool and not, say, a solver like x402-sudoku-solve or a move tool like x402-2048-move. It stops short of distinguishing which of the two operations is which in the 11-parameter surface, but the purpose itself is clear.

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?

There is no guidance on when to use this versus anything else, no statement of prerequisites, and crucially no indication that the tool has two distinct modes (generate vs. reveal) that pick different parameters. An agent must guess from parameter names alone which call pattern applies.

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