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

Annotations already declare destructiveHint=false and openWorldHint=true, but the description adds substantive behavior: the hard guarantee that destructive or spending tools are never run, that an ack from agentmart_tools is mandatory, and that a block on the underlying single tools does not carry over at /mcp/core. It stops short of describing what is returned on failure or whether the wrapped call's errors are surfaced.

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?

Purpose and the destructive/spend guard are front-loaded in the first sentence, and every sentence carries load-bearing information. The final sentence, however, is a long semicolon-spliced construction about /mcp/core routing that takes effort to parse and slightly muddies the otherwise crisp opening.

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 router tool with a nested free-form arguments object and no output schema, the description covers selection, the required ack handshake, the safety envelope and deployment-specific routing. What's missing is what a call returns or how wrapped-tool failures are reported, though the schema's ack description partially covers that.

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 the schema already documents ack, tool, arguments and passport_token in detail, including the enum. The description only restates the triple of tool/ack/arguments and adds no syntax or format detail beyond that, so the 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 ("Run one AgentMart tool") plus the precise scope of what it will and won't execute: changes or reaches outside, never destroys or spends. An agent can distinguish it from agentmart_read, agentmart_tools and buy without opening any schema.

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 names the condition for use (a tool not in your list), the exclusion (a tool in your list, such as buy, should be called directly), and the alternative for non-mutating calls (agentmart_read). It also gives routing guidance for /mcp/core versus /mcp, which is exactly the kind of when-to-use context an agent needs.

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