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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the agent knows it's safe. The description adds value by specifying the DPX-tagging behavior (memo contains 'dpx:') and the data fields returned, which aids in understanding the tool's output beyond the schema.

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 concise (three sentences) and front-loaded with the essential purpose. Every sentence adds value: first sentence states action and output, second sentence provides filtering context, third sentence gives a concrete use case.

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?

Given the output schema exists, the description doesn't need to explain return values further. The tool is simple (3 params, 1 required) and the description covers its purpose, usage prerequisites, and a specific reconciliation use case, making it complete for this context.

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 coverage is 100% and the schema already describes all parameters clearly (limit, offset, accountId). The description adds a small amount of context (account ID from mercury.accounts, default/max for limit) but doesn't significantly extend the schema's meaning. Baseline 3 is appropriate.

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 clearly states the tool lists recent transactions for a Mercury bank account and specifies the exact data returned (transaction ID, amount, status, etc.). It distinguishes itself from sibling tools like mercury.accounts and mercury.send by focusing on transaction listing.

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 description explicitly tells when to use this tool (to reconcile DPX settlements against Mercury bank activity), provides a prerequisite (account ID from mercury.accounts), and implies it's for read-only verification rather than sending/sweeping money, differentiating it from siblings like mercury.send and mercury.sweep.

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