city.listList US City Open-Data Compliance Network cities with paid_url, sample_url, and price. Call first, then city.sample, then city.check for the paid address lookup.
| Name | Required | Description | Default |
|---|---|---|---|
| agent_id | No | Optional agent identity for quota accounting. |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover read-only, idempotent, and non-destructive behavior, so the description is not required to restate those. It adds useful behavioral context by disclosing that the list exposes paid_url, sample_url, and price data, and by identifying the overall paid-address-lookup workflow.
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 two sentences with no filler. It front-loads the core purpose and data fields, then immediately gives the workflow order needed to use the related city.* tools correctly.
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, read-only list tool with zero required parameters and an output schema available, the description is complete. It provides the listed fields, the meaningful sequencing instructions, and enough context for an agent to select and invoke it correctly.
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%, and the only parameter, agent_id, is already documented as an optional identity for quota accounting. The description doesn't add any parameter-level detail, so the baseline score of 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 uses a specific verb (list) with a specific resource (US City Open-Data Compliance Network cities) and clearly states the fields returned (paid_url, sample_url, price). It is immediately distinguishable from the sibling city.sample and city.check tools because it positions itself as the introductory listing step.
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 gives explicit workflow guidance: call this tool first, then city.sample, then city.check. This tells the agent exactly when and in what order to use this tool relative to its relevant siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
The namespaces help, but there is real overlap in purpose: city.check with x402.pay_and_fetch, city.sample with x402.probe, and multiple tools that verify a payment and then activate, credit, or settle something. The descriptions clarify which resource is being paid for, but tool names alone leave room for misselection.
Nearly every tool uses a lower-case dotted namespace.action pattern, making the set easy to scan. Some command parts are inconsistent, though: x402.networks, pulse.base, and commerce.credits_requirements read as nouns rather than actions, so the style is mostly but not fully uniform.
Nineteen tools is in the heavy range, and they span many subsystems: x402, city, commerce/quotas, swarm, ops, and Base network metrics. The number is not extreme, but the server feels like multiple product surfaces bundled under one MCP rather than a tightly scoped toolset.
The x402 lifecycle is well covered: discover, probe, pay, fetch, verify, sell, and settle, plus supportive commerce and city workflows. Notable gaps are refunds/quota-balance checks, seller resource update/removal, and invoice-like management for Stripe/card purchases, but none blocks the object workflows.