verifiable_fetchFetch a URL as readable text AND get a receipt anchoring a hash of the exact bytes returned, so you can later prove what the page said when you read it. Priced per call (pay over HTTP with an x402 payment — see /pay).
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | the page to fetch | |
| thorough | No | wait for lazy-loaded content |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the full behavioral disclosure burden. It mentions pricing and the x402 payment mechanism, which is helpful, but it fails to disclose side effects (e.g., whether receipts are stored), rate limits, authentication requirements, or handling of redirects/errors. The fetch is read-only implied but not explicitly stated, and there's no mention of response structure or failure modes.
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, front-loaded with the core purpose and proof feature, followed by the payment note. Every sentence contributes value, and there is no redundant or filler content. It is appropriately sized for a simple tool with two parameters.
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 lack of an output schema, the description should explain what the agent can expect as a return value. It says 'readable text' and 'receipt' but does not specify the response format, how to interpret the receipt, or error/payment failure handling. The tool has moderate complexity (payment, proof generation), and this description leaves important details unspecified, though it is not entirely inadequate.
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% for both parameters (url and thorough), so the baseline is 3. The description adds minimal extra meaning: it implies 'url' is the target and 'thorough' waits for lazy content, but these are already in the schema. It does not clarify default behavior or edge cases beyond the schema's simple descriptions.
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 (fetch) with a clear resource (URL) and adds the unique value proposition of returning a proof receipt via hash anchoring. It clearly distinguishes this from sibling tools like archive_url or verify_hash by focusing on fetching with verifiability, making the purpose specific and unambiguous.
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 implies when to use this tool: when you need to prove what a page said at fetch time. It also notes payment is required, which is a condition for use. However, it does not explicitly name alternatives or state when not to use it, though the context (need for proof) is clear enough for most agents to differentiate.
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.
Each tool has a distinct purpose: capturing pages, anchoring hashes individually or in batches, fetching and verifying, and checking system status. There is no overlap or confusion between tools.
All tool names use snake_case with descriptive verbs and nouns (e.g., archive_url, notarize_hash, verify_hash), following a consistent and predictable pattern.
With 7 tools, the set is well-scoped for a notarization and archiving service, covering core operations without being overly sparse or bloated.
The tool surface covers the full lifecycle of timestamping and verification: single hash notarization, batch anchoring, web page capture, verifiable fetch, lookup by hash, and service status. No obvious gaps remain.