Agentic Hub · Devcon Mumbai

Before an agent pays you, it has to find you.

How agents discover each other, and why discovery is secretly an identity problem

agent search

"weather api, pays per call"

W

WeatherProweatherpro.xyz

✓

W

WeatherProweatherpr0.xyz

?

W

WeatherPro Officialagent #81,224

?

WHICH ONE?

Who's talking

Vedant
Anand

Co-founder & CTO, Bagsx402 contributor@vedantsx

getbags.appAPIs agents pay for

gtmmaxing.comsales data, per call

On today's menu

the standards we'll unpack

A2A Agent Cardsfind

MCP Registryfind

x402 Bazaarfind

ERC-8004 + ENSverify

Web Bot Authverify

ALL LIVE

02

The problem

3:07 AM. Nobody is awake.

03

We've done this before

We solved this once. For humans.

For humansFor agents

Yellow pages, Googlewhere do I look?

→

Registries & indexesMCP Registry · x402 Bazaar · ERC-8004

Shop sign, homepagewhat do you do?

→

Agent Cards/.well-known/agent-card.json

Domain + padlockis this really you?

→

ENS + keys + ERC-8004names, signatures, on-chain records

Reviews, PageRankare you any good?

→

Reputation & validationfeedback, stake, attestations

04

Goal: anchor every new idea to something they already know. This is the whole talk in one slide.

"Good news: we've solved this before, for humans. It took the web about thirty years."

[click] "Where do I look? For us it was the yellow pages, then Yahoo, then Google. For agents it's registries and indexes."

[click] "What do you do? For us, a shop sign or a homepage. For agents, a small JSON file called an Agent Card."

[click] "Is this really you? For us, the domain name and the padlock in the browser. For agents: ENS names, cryptographic keys, and on-chain records."

[click] "Are you any good? For us, reviews and Google's PageRank. For agents, reputation and validation."

"Same four questions. New plumbing. Let's walk through each."

Today's map

Four stops, one search at 3:07 AM.

05

Stop 1 · Find

There are only three ways to find anything.

Knock on the door

You know the domain. Fetch a file at a fixed path.

GET weatherpro.xyz
/.well-known/
agent-card.json

Ask a directory

Someone keeps a list. You search it.

MCP Registry
x402 Bazaar
ERC-8004 indexers

Ask the network

Resolve a name, or broadcast and see who answers.

ENS records
DNS-SD for A2A (draft)

06

Goal: a simple taxonomy that every later protocol fits into.

"Here's a fact that makes this whole space easier: there are only three ways to find anything, on the web or anywhere else."

[click] "One: you already know the address, so you knock on the door. For agents that's a file at a fixed path on a domain, a so-called well-known URL. Cheap, but you need to know the domain first."

[click] "Two: you ask a directory. Someone keeps a list and you search it. The official MCP Registry, Coinbase's x402 Bazaar, and the indexers built on ERC-8004 all live here."

[click] "Three: you ask the network. Resolve a name like an ENS name, or broadcast on a local network and see who answers. There's an IETF draft for doing this with A2A over DNS."

"Every protocol you'll hear about this week is one of these three, or a mix."

Stop 1 · Find

Every domain now has doors for machines.

07

Goal: make "well-known URL" concrete and visual.

"Let's zoom into 'knock on the door'. There's an old internet rule, RFC 8615, that says: if you want a standard file every site can publish, put it under slash dot-well-known. Think of it as doors on a building, each one for a different kind of visitor."

[click] "The A2A door: agent-card.json. Google's agent-to-agent protocol. It says what this agent can do. Note: older cards still sit at agent.json, and about a quarter of providers in one July survey were still on the old path."

[click] "The MCP door, for tool servers. This one is still settling. There's a server.json the official registry can pick up, and a server-card proposal that's still a draft."

[click] "The ERC-8004 door. Remember this one, it's how a domain proves it belongs to an on-chain agent. We'll come back to it."

[click] "This one is the reverse: where an agent publishes its signing keys, so websites can recognise it. Also coming back later."

[click] "And llms.txt, a plain-text guide for language models. Not a standard, but widely used."

Stop 2 · Describe

An Agent Card is a business card for machines.

W

WeatherPro

hyperlocal forecasts, by the call

Skillsforecast · alerts

Calla2a.weatherpro.xyz

AuthOAuth · x402

// /.well-known/agent-card.json
{
  "name": "WeatherPro",
  "description": "Hyperlocal forecasts",
  "url": "https://a2a.weatherpro.xyz",
  "skills": [
    { "id": "forecast", "tags": ["weather"] }
  ],
  "securitySchemes": { … }
}

Notice what's missing: nothing proves who wrote it.

08

Stop 2 · Describe

The x402 Bazaar: a directory built from receipts.

Listed only after a real payment: proof somebody used it.

09

Goal: show a directory with a built-in honesty signal. This is the bridge from discovery to identity.

"Now a directory that's specific to paid APIs: the x402 Bazaar, run by Coinbase's facilitator and copied by others like Binance. Same four players as any x402 payment."

[click] "The API answers 402, payment required. In that answer it says the price, and with the Bazaar extension, an example input and output schema, so a machine knows how to call it."

[click] "The agent pays, and echoes that description back inside its payment."

[click] "The facilitator verifies and settles, like any x402 payment."

[click] "And then it adds the endpoint to the catalog. Agents search it at slash discovery slash resources, over REST or through an MCP tool."

[click] "Here's the clever bit: you only get listed after a real payment went through. It's a directory built from receipts. Coinbase calls it 'Yahoo search' for now. Honest description. Keep 'receipts' in mind, it comes back as the answer at the end."

Pop quiz

Who wrote "Uniswap Official"?

A

Uniswap

B

Anyone with a web server

✓

C

The registry checked

UNVERIFIED

10

The one idea to take home

Discovery is a claim.
Identity makes it checkable.

11

Stop 3 · Verify

"Identity" is really three different things.

@

A name

How others point at you.

weatherpro.eth
weatherpro.xyz

A key

How you prove each message is yours.

wallet signature
Ed25519 key

A record

A public entry anyone can look up and index.

ERC-8004 agent #42

12

Stop 3 · Verify

ERC-8004: every agent is an NFT with a résumé.

13

Goal: make ERC-8004's Identity Registry tangible. It's simpler than people think.

"ERC-8004, 'Trustless Agents'. Written by people from MetaMask, the Ethereum Foundation, Google and Coinbase. Still a draft, but deployed on Ethereum mainnet since January and on twenty-plus chains."

[click] "The trick is boring on purpose: every agent is an NFT. A plain ERC-721 token. Number 42. Whoever owns the token owns the agent. That means you can transfer it, put it in a multisig, and every wallet and explorer already understands it."

[click] "The token points to a file, the agentURI. Think of it as the agent's résumé: its name, and a list of services. Here's my A2A card, here's my MCP server, here's my ENS name. Plus a flag for 'I accept x402', and which trust models I support."

[click] "So the NFT becomes the hub that links all the discovery doors we just saw."

[click] "And it gets a global ID: chain, registry address, token number. Any indexer on any chain can refer to this exact agent without ambiguity."

"But here's the subtle part. This file is still just a claim. I can list weatherpro dot eth in my résumé without owning it. So how do we close the loop?"

Stop 3 · Verify

A link counts only when both sides point back.

14

Goal: the core mechanism of verification. Two-way binding. This is the "aha" slide for the top 10%.

"Here's the rule that makes all of this work, and it's the same rule as a handshake: a link only counts when both sides agree."

[click] "The ENS side. ENSIP-25, shipped this March. The owner of weatherpro dot eth sets a text record that literally says 'agent-registration, this registry, agent 42, yes'. Now the record points to the name, and the name points back. Verified."

[click] "The domain side. ERC-8004 lets you put a file at slash dot-well-known slash agent-registration dot json on your domain, listing your agent ID. Only someone who controls the domain can put it there."

[click] "The wallet side. The wallet that receives payments can't just be typed in. The wallet itself has to sign, EIP-712 for normal wallets, ERC-1271 for smart wallets."

[click] "Two details that matter. If you sell or transfer the NFT, the wallet link is cleared, so a new owner can't silently redirect payments. And if only one side makes the claim, a good client treats it as unverified."

"Name, domain, wallet: three handshakes around one record. That's what 'verified' should mean."

Stop 3 · Verify

Sites need to discover agents, too.

GET /forecast?city=mumbai

Signature-Agent: "https://agent.bags.xyz"

Signature-Input: sig=(…);keyid="…";tag="web-bot-auth"

Signature: sig=:MEUCIQD9…:

Cloudflare
"signed agents"let in

Visa TAP
agent-browser-auth
agent-payer-authbrowse / pay

x402 SIWX
"I paid already"no repay

15

Goal: discovery is two-sided. Services must recognise agents, or they'll block them as bots.

"So far our agent has been checking the service. But the service is also asking: who is this agent? Is it a scraper, or a real customer's assistant? Today most sites just block anything that isn't a browser."

[click] "Web Bot Auth fixes this, an IETF working group draft built on RFC 9421, HTTP message signatures. The agent adds a header, Signature-Agent, that says where its keys live."

[click] "Then it signs the request itself, with a tag that says 'web-bot-auth'. Short-lived, so it can't be replayed later."

[click] "The site reads the header, fetches the agent's public keys from that well-known door we saw earlier, and checks the signature. Now it knows exactly which operator sent this request."

[click] "Cloudflare uses this for its 'signed agents' category, so verified agents get through instead of getting a captcha."

[click] "Visa's Trusted Agent Protocol builds on the same signatures, with two tags: one for 'I'm just browsing', one for 'I'm about to pay'. Mastercard Agent Pay is similar."

[click] "And in x402, Sign-In-With-X lets an agent say 'I already paid for this, here's a signature from that wallet', so it doesn't pay twice. Identity from payment history."

Stop 4 · Trust

Real is not the same as good.

Reputation

What others said

Clients leave on-chain feedback after using it.

cost to fake: low

Stake

What they'd lose

Money locked up, slashed if they cheat.

cost to fake: the stake

Attestation

Proof it ran

A TEE or zk proof that the right code ran.

cost to fake: very high

16

Goal: separate "real" from "good". Introduce cost-to-fake as the lens.

"Say WeatherPro passes every check. It's real. Is it good? Are the forecasts accurate? Does it go down every night? Identity can't answer that. That's the trust layer, and ERC-8004 has two more registries for it."

[click] "Reputation: clients who used the agent leave feedback on-chain. A score, a couple of tags, and a link to details. Like Google reviews. Cheap to leave, which means cheap to fake."

[click] "Stake: the agent locks up money that gets slashed if a validator catches it cheating. Now lying costs something."

[click] "Attestation: a trusted execution environment, or a zero-knowledge proof, shows the exact code that ran. Hardest to fake, but more setup."

"Notice the line at the bottom of each card. That's the only question that matters in trust: how much does it cost to fake this signal? Let's look at what happens when it's cheap."

Stop 4 · Trust

Reality check: cheap reviews get faked.

173k

agents registered on Ethereum, Base and BSC

3–15%

have a valid file and a declared endpoint

90.6%

of reviewers on Base look like Sybils

$0.003

to post one fake review on Base

One fake review is usually enough to push an agent past a trust threshold.

Source: "Can Trustless Agents Be Trusted?" arXiv 2606.26028, data through 13 May 2026

17

Goal: honest data. This is what separates a serious talk from a hype talk. The top 10% will respect this.

"Here's real data, from a paper this summer that crawled every ERC-8004 registration on Ethereum, Base and BSC through May."

[click] "About 173 thousand agents registered. Sounds like a thriving ecosystem."

[click] "But only 3 percent on Ethereum, 4 on BSC, 15 on Base have a valid registration file with even one service endpoint declared. Most are placeholders: name squatting, airdrop farming."

[click] "On Base, over 90 percent of the wallets leaving reviews look like Sybils, clusters funded from the same source."

[click] "Because a review costs about a third of a cent to post. The rule that you can't review your own agent is bypassed by funding a fresh wallet."

[click] "And one fake review is usually enough to tip an agent over a trust threshold. The authors' conclusion: as deployed, the reputation registry can't work as a trust signal on its own. The spec actually warns about this; it forces you to choose whose reviews you count."

"So the problem isn't the registry. It's that a review costs nothing. How do we make it cost something?"

Stop 4 · Trust

Only count reviews that cost something.

Review

agent #42 · WeatherPro

Score★★★★★

Fromfresh wallet

Paid WeatherPronever

COST TO POST$0.003

IGNORED

Review

agent #42 · WeatherPro

Score★★★★☆

From0xC4r…ol

x402 receipts31 calls

PAID FIRST$12.40

COUNTED

18

Goal: the resolution. Payments are the costly signal, which is exactly where discovery, identity and x402 meet.

"The fix is the same thing Google did to Yahoo. Yahoo listed whoever asked. Google counted links, which were costly to fake. We need a costly signal for agents. And we already have one: money."

[click] "Here's a five-star review from a wallet that was created yesterday and never paid WeatherPro a cent. It cost a third of a cent to post."

[click] "Ignore it."

[click] "Here's a four-star review from a wallet with thirty-one x402 payment receipts to WeatherPro, twelve dollars spent. ERC-8004 feedback has a field for a link to evidence, so the review can point at those receipts."

[click] "This one counts. To fake it, you have to actually pay, and the more weight you want, the more you pay."

"That's the full circle: the Bazaar lists you because someone paid; reputation counts because someone paid. Payments aren't just the end of discovery. They're the proof that makes discovery honest."

All together

3:07 AM, solved.

19

Goal: the payoff. Replay the 3 AM story with every piece in place.

"Back to 3:07 AM. Here's what a well-built agent does, with everything we learned."

[click] "One: it searches an index. Bazaar, the MCP Registry, or an ERC-8004 indexer. FIND."

[click] "Two: it gets back a card and an agent ID. DESCRIBE."

[click] "Three: it checks the handshakes on chain. Does the ENS name point back? Does the domain list agent 42? Did the wallet sign? VERIFY. This is where the two fake WeatherPros from slide one fall out."

[click] "Four: it reads reputation, but only counts reviewers who have paid receipts. TRUST."

[click] "Five: it calls the API with a signed request, so WeatherPro knows which agent this is and doesn't block it."

[click] "Six: normal x402. 402, pay, 200 with a receipt."

[click] "Seven: it leaves feedback that links that receipt, which makes the next agent's search a little more honest. The loop closes itself."

Check yourself

Three questions you can now answer.

1Where does an A2A agent card live?
/.well-known/agent-card.json on its domain

2Why isn't an ERC-8004 NFT alone proof of anything?
It's a claim until the ENS name, domain and wallet point back

3What makes a review worth counting?
It was expensive to fake: tied to real payments, stake or proofs

20

If you build agents or APIs

Three things to ship on Monday.

Publish your doors

agent-card.json or server.json, and turn on x402 Bazaar discovery

Register, then bind both ways

ERC-8004 record + ENSIP-25 text record + agent-registration.json on your domain

Sign requests, link receipts

Web Bot Auth on outbound calls; feedback that points at x402 receipts

21

Thank you · questions?

Discovery is a claim. Make yours checkable.

Vedant Anand · @vedantsx · @getbagsapp

agent #42

weatherpro.eth

ENS points back✓

Domain points back✓

Wallet signed✓

Paid reviews31

VERIFIED

Before an agent pays you, it has to find you.

agent search

VedantAnand

On today's menu

3:07 AM. Nobody is awake.

We solved this once. For humans.

Four stops, one search at 3:07 AM.

There are only three ways to find anything.

Knock on the door

Ask a directory

Ask the network

Every domain now has doors for machines.

An Agent Card is a business card for machines.

WeatherPro

The x402 Bazaar: a directory built from receipts.

Who wrote "Uniswap Official"?

Uniswap

Anyone with a web server

The registry checked

Discovery is a claim.Identity makes it checkable.

"Identity" is really three different things.

A name

A key

A record

ERC-8004: every agent is an NFT with a résumé.

A link counts only when both sides point back.

Sites need to discover agents, too.

Real is not the same as good.

What others said

What they'd lose

Proof it ran

Reality check: cheap reviews get faked.

Only count reviews that cost something.

Review

Review

3:07 AM, solved.

Three questions you can now answer.

Three things to ship on Monday.

Publish your doors

Register, then bind both ways

Sign requests, link receipts

Discovery is a claim. Make yours checkable.

agent #42

Vedant
Anand

Discovery is a claim.
Identity makes it checkable.