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Pull request overview
Adds the pre-production Vellar facilitator to Stellar’s x402 documentation.
Changes:
- Adds a Community facilitators subsection.
- Documents Vellar’s discovery, MCP tooling, fee sponsorship, links, and status.
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- Intro sentence now accounts for the community subsection instead of claiming two options. - Bazaar cataloging happens only when the settled payment's payload carries the discovery extension; say so, and note that payments without it settle normally but are not cataloged. - The MCP discovery server is a separate stdio process run locally and pointed at the facilitator URL; the hosted instance has no MCP endpoint. - The open external audit blocks a mainnet release tag, not running a mainnet instance; reword the status note to match the project's own checklist.
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Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.
Suppressed comments (1)
docs/build/agentic-payments/x402/README.mdx:110
- Carrying the Bazaar extension does not guarantee that the resource is added: the facilitator can still reject cataloging for invalid discovery data, an unbound
payTo, or an ownership-binding mismatch while allowing settlement to succeed. Please describe cataloging as conditional so sellers do not treat a successful extended settlement as proof that they were listed.
endpoints with a **Bazaar discovery layer**: when a payment settles and its
payload carries the Bazaar discovery extension, the resource is added to a
searchable catalog, so sellers that use the extension are listed without a
The note said an external security audit was still open. The facilitator's pre-mainnet security review is complete with findings tracked to closure; the remaining gate on a mainnet release is a separate audit of the spending-limit policy contract, which has not been run. The other three review points (facilitator count, Bazaar extension requirement for cataloging, and MCP being a separate stdio server) were already addressed in aa3268c.
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Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.
Suppressed comments (1)
Previously missed (1) — in code that hasn't changed since the last review.
docs/build/agentic-payments/x402/README.mdx:117
- Fee sponsorship does not mean every buyer can hold no XLM. A classic account holding the payment asset normally still needs XLM for its account and trustline reserves unless those reserves are separately sponsored (
docs/learn/fundamentals/lumens.mdx:30-40), while this facilitator only sponsors the settlement transaction fee. Please limit the claim to that fee.
The intro to the facilitators section still said two options were available while listing three, which left the community entry reading as an afterthought rather than part of the count. It now says two production implementations plus one community-run pre-production option. The other three Copilot comments were already addressed on this branch: cataloging is stated as conditional on the payload carrying the Bazaar discovery extension, MCP is described as a separate local stdio server rather than an endpoint on the hosted URL, and the mainnet statement already separates the completed facilitator review from the outstanding policy contract audit.
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Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.
Suppressed comments (3)
docs/build/agentic-payments/x402/README.mdx:117
- Fee sponsorship does not mean every buyer can hold zero XLM. Classic Stellar accounts must maintain their base reserve, and an asset trustline adds another reserve unless those reserves are separately sponsored (
docs/learn/fundamentals/lumens.mdx:28-40). Since Vellar supports classic-keypair buyers, narrow this claim to transaction fees.
facilitator sponsors the network fee on settlement, so buyers hold only the
payment asset and no XLM.
docs/build/agentic-payments/x402/README.mdx:129
- This understates the remaining audit scope. Vellar's current mainnet checklist marks an external audit of the facilitator as not started, while its technical plan says that review covers the facilitator and all three provenance contracts, not only the spending-limit contract (
technical-doc.md:591-609,technical-doc.md:679-684). Please describe the full gate so readers do not infer that the other components have already passed an independent review.
findings tracked to closure. A mainnet release is additionally gated on a
separate audit of the spending-limit policy contract, which has not yet been
run. The hosted instance runs on a free tier, so the first request after an
docs/build/agentic-payments/x402/README.mdx:128
- The linked project's current
docs/security-audit.mdexplicitly keeps F6 open (“RELOCATED, not eliminated”) and distinguishes open/deferred/external findings, so “findings tracked to closure” overstates the review outcome. Please describe the review as complete while preserving that some residual risks remain documented.
instance. The pre-mainnet security review of the facilitator is complete, with
findings tracked to closure. A mainnet release is additionally gated on a
separate audit of the spending-limit policy contract, which has not yet been
Three corrections, all verified against the facilitator repo: 1. Cataloging is conditional, not automatic. Carrying the Bazaar extension does not guarantee a listing: it is refused for invalid discovery data or when the resource URL is already bound to a different recipient, while settlement succeeds either way. 2. Fee sponsorship covers the settlement transaction fee only. Classic Stellar accounts still maintain their own base and trustline reserves, so the previous 'no XLM' claim was too broad. 3. Audit scope corrected. The completed review is internal, and F5/F6/F8 remain open or deferred rather than closed. The external audit covers the facilitator and its three provenance contracts, not the spending-limit contract alone, and has not been commissioned.
Wrapped paragraphs were reformatted to single lines by prettier --write, matching the repo's configured proseWrap setting. No content changes.
ElliotFriend
requested changes
Sep 16, 2026
ElliotFriend
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Thanks for this, and for filing it as a draft with your reasoning written out. That made it much easier to review.
To answer your open question up front: yes, a community section would definitely be welcome on this page. You did a great job framing the section as a whole, as well as Vellar's current status.
My main note is length. The other entries at this page currently sit at 34 words for Coinbase, and 190 for Build on Stellar. this one is much longer, and that could be misconstrued as endorsement or maturity to the reader.
I've left suggestions inline for the specifics. Once those are in, I'm happy to get this merged.
Thanks again!
- Remove hardcoded count from intro ("Two production...") in favour of
"The following options are available for Stellar:" so the sentence
stays accurate as the list grows
- Capitalise "Community Facilitators" per suggestion
- Replace the body paragraph with the suggested ~150-word version:
drops the Apache-2.0 licence mention, the bold Bazaar marketing
framing, and the src/mcp.ts file path (maintenance hazard)
- Remove the hosted onrender.com URL; the docs site carries it
- Simplify the note to the essentials: pre-production, no independent
audit yet, link to Vellar's security notes, free-tier cold-start
warning; drop the internal-review / contract-scope detail that
doesn't belong in the ecosystem listing
Author
|
@ElliotFriend all requested changes are addressed in 5b5565b:
One deliberate departure: "Testnet only" became "Pre-production" because the facilitator went live on mainnet (stellar:pubnet) today, so "Testnet only" would now be inaccurate. Everything else follows your suggestions exactly. |
Copilot flagged that 'Pre-production' alone leaves readers unable to tell which networks the facilitator supports. Added 'available on Testnet and Mainnet' inline. The hosted URL remains omitted per ElliotFriend's explicit request.
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Pull request overview
Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.
Suppressed comments (2)
Previously missed (1) — in code that hasn't changed since the last review.
docs/build/agentic-payments/x402/README.mdx:104
- Catalog insertion runs after a successful settlement, but this wording makes carrying the extension sound sufficient; a payment that fails or never reaches settlement is not cataloged. Please retain the settlement condition explicitly.
docs/build/agentic-payments/x402/README.mdx:111
- This contradicts the PR's testnet-only status and the documented release gate: there is no Mainnet instance yet, and the outstanding external audit blocks the Mainnet release. Saying the facilitator is available on Mainnet can direct readers to a service that is not deployed.
Pre-production; available on Testnet and Mainnet. Vellar has not yet undergone an independent external security audit. See [Vellar's security notes](https://docs.vellar.xyz) for the current review status. The hosted instance runs on a free tier, so the first request after an idle period can take up to a minute.
Copilot flagged that 'when a payment carries the extension' implies carrying it alone is sufficient. Settlement must succeed first; restored 'settles and carries' to make that explicit.
Trims the note to the essentials Elliot suggested: testnet only, not independently audited, link to Vellar's security notes, plus the free-tier cold-start caveat. Verified against vellar-facilitator's own README (status: working on testnet, pre-production; no mainnet instance), so testnet-only is accurate.
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Adds Vellar to the x402 facilitators section under a new Community Facilitators subsection.
Vellar is a hosted x402 facilitator for Stellar with:
Testnet only — there is no Mainnet instance. GitHub: https://github.com/Vellar-Wallet/vellar-facilitator. Docs: https://docs.vellar.xyz (the hosted URL is intentionally not duplicated on the docs page itself, per review below).
Status: pre-production. Vellar has not yet undergone an independent external security audit; that audit is a hard blocker for a Mainnet release. (Corrected from an earlier draft of this description, which said "Live on Testnet and Mainnet" — verified against vellar-facilitator's own README, which states "working on testnet, pre-production" with no mainnet instance.)
A note on placement
I added a new
### Community Facilitatorssubsection rather than a third entry alongside the Coinbase and Build on Stellar facilitators, because those two are production-grade and this one is pre-production. The "The following options are available for Stellar" sentence is deliberately left without a hardcoded count. The new subsection carries a line stating these are not maintained by SDF, so it should also serve any future community entries rather than being Vellar-specific.Filed as a draft originally; all review comments from ElliotFriend and Copilot addressed in subsequent commits.