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x402 & HTTP 402 Explained: Why Wallet-Paid API Calls Are Winning (and Where Token Metrics Fits)

The definitive guide to x402, the HTTP-native payment protocol enabling AI agents to pay for APIs per call. Includes ecosystem proof, technical implementation, and Token Metrics integration details.
Token Metrics Team
10 min read
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What Is x402?

x402 is an open-source, HTTP-native payment protocol developed by Coinbase that enables pay-per-call API access using crypto wallets. It leverages the HTTP 402 Payment Required status code to create seamless, keyless API payments.

It eliminates traditional API keys and subscriptions, allowing agents and applications to pay for exactly what they use in real time. It works across Base and Solana with USDC and selected native tokens such as TMAI.

Start using Token Metrics X402 integration here. https://www.x402scan.com/server/244415a1-d172-4867-ac30-6af563fd4d25 

TLDR — The x402 Value Proposition

x402 transforms API access by making payments native to HTTP requests.

Feature

Traditional APIs

x402 APIs

Authentication

API keys, tokens

Wallet signature

Payment Model

Subscription, prepaid

Pay-per-call

Onboarding

Sign up, KYC, billing

Connect wallet

Rate Limits

Fixed tiers

Economic (pay more = more access)

Commitment

Monthly/annual

Zero, per-call only

How to use it: Add x-coinbase-402: true header to any supported endpoint. Sign payment with your wallet. The API responds immediately after confirming micro-payment.

Token Metrics integration: All public endpoints available via x402 with per-call pricing from $0.017 to $0.068 USDC (10% discount with TMAI token).

Explore live agents: https://www.x402scan.com/composer.

How HTTP 402 Payment Required Works — Technical Deep Dive

The Protocol Flow

The HTTP 402 status code was reserved in HTTP/1.1 in 1997 for future digital payment use cases and was never standardized for any specific payment scheme. x402 activates this path by using 402 responses to coordinate crypto payments during API requests.

  1. Step by step: Client makes an API request with the header x-coinbase-402: true.
  2. The server can return 402 with payment details such as amount, recipient, and chain.
  3. The client wallet signs and submits the payment transaction.
  4. The server verifies the payment on-chain, then processes the original request and returns 200 with data.

Why this matters: It eliminates intermediary payment processors, enables true machine-to-machine commerce, and reduces friction for AI agents.

Ecosystem Proof: x402 Is Winning — Three Validation Points

CoinGecko Recognition

CoinGecko launched a dedicated x402 Ecosystem category in October 2025, tracking 700+ projects with over $1 billion market cap and approximately $213 million in daily trading volume. Top performers include PING and Alnalyst, along with established projects like EigenCloud.

  

Base Network Adoption

Base has emerged as the primary chain for x402 adoption, with 450,000+ weekly transactions by late October 2025, up from near-zero in May. This growth demonstrates real agent and developer usage.

x402scan Composer — Where Agents Pay in Real Time

Composer is x402scan's sandbox for discovering and using AI agents that pay per tool call. Users can open any agent, chat with it, and watch tool calls and payments stream in real time.

Top agents include AInalyst, Canza, SOSA, and NewEra. The Composer feed shows live activity across all agents.

  

Explore Composer: https://x402scan.com/composer 

Token Metrics x402 Integration — Concrete Implementation

What We Ship

Token Metrics offers all public API endpoints via x402 with no API key required. Pay per call with USDC or TMAI for a 10 percent discount. Access includes trading signals, price predictions, fundamental grades, technology scores, indices data, and the AI chatbot.

Check out Token Metrics Integration on X402. https://www.x402scan.com/server/244415a1-d172-4867-ac30-6af563fd4d25 

  

Data as of October, 2025.

Pricing Tiers

  

  

Important note: TMAI Spend Limit: TMAI has 18 decimals. Set max payment to avoid overspending. Example: 200 TMAI = 200 * (10 ** 18) in base units.

Full integration guide: https://api.tokenmetrics.com 

Why x402 Changes Everything for AI Agents

  • Eliminates onboarding friction. Agents can discover and use new APIs instantly without human intervention for API key management or billing setup.
  • Enables true agentic commerce. Agents pay for exactly what they use, which makes micro-transactions economically viable. This unlocks composition of multiple specialized services.
  • Aligns incentives. API providers get paid per call, users only pay for value received, and agents can optimize costs by choosing best-fit providers. Network effects accelerate as more endpoints adopt x402.

Use Cases Already Working

  • Crypto analytics agents: Pull Token Metrics data on demand to answer market questions, generate trade signals, or build custom dashboards.
  • Research automation: Chain together x402 endpoints like Twitter search, Tavily extract, Firecrawl, and Token Metrics to gather and structure data.
  • Portfolio management: Agents monitor positions, fetch real-time prices, calculate risk metrics, and execute rebalancing decisions using paid data sources.
  • Trading strategy backtests: Access historical OHLCV, grades, and signals data via x402 without committing to monthly subscriptions.
  • Multi-chain intelligence: Combine Base and Solana x402 services for cross-chain analysis and arbitrage discovery.

Ecosystem Participants and Tools

Active x402 Endpoints

Key endpoints beyond Token Metrics include Heurist Mesh for crypto intelligence, Tavily extract for structured web content, Firecrawl search for SERP and scraping, Twitter or X search for social discovery, and various DeFi and market data providers.

Infrastructure and Tools

  • x402scan: Explorer and analytics platform tracking all x402 activity across chains.
  • Composer: Hosted sandbox for discovering and using x402-enabled agents.
  • x402-axios and x402-httpx: Client libraries for Node.js and Python.
  • Coinbase Agent Kit: SDK integration for building x402-native agents.
  • LangChain connectors: Framework integration for agent workflows.

Common Questions About x402

How is x402 different from traditional API keys?

x402 uses wallet signatures instead of API keys. Payment happens per call rather than via subscription. No sign-up, no monthly billing, no rate limit tiers. You pay for exactly what you use.

Which chains support x402?

Currently Base and Solana. Most activity is on Base with USDC as the primary payment token. Some endpoints accept native tokens like TMAI for discounts.

Do I need to trust the API provider with my funds?

No. Payments are on-chain and verifiable. You approve each transaction amount. No escrow or prepayment is required.

What happens if a payment fails?

The API returns 402 Payment Required again with updated payment details. Your client retries automatically. You do not receive data until payment confirms.

Can I use x402 with existing API clients?

Yes, with x402 client libraries such as x402-axios for Node and x402-httpx for Python. These wrap standard HTTP clients and handle the payment flow automatically.

Getting Started Checklist

  1. Set up a wallet: Create a Base wallet with USDC or TMAI balance.
  2. Install x402 client: npm install x402-axios or pip install x402-httpx.
  3. Choose an endpoint: Browse x402scan or Composer for available APIs.
  4. Write minimal code: Add x-coinbase-402: true header to requests.
  5. Watch payments flow: Monitor transactions in your wallet and on x402scan feed.
  6. Optimize costs: Compare endpoint pricing, use TMAI for 10% discount, cache results when appropriate.

Token Metrics x402 Resources

What's Next for x402

Ecosystem expansion. More API providers adopting x402, additional chains beyond Base and Solana, standardization of payment headers and response formats.

Agent sophistication. As x402 matures, expect agents that automatically discover and compose multiple paid endpoints, optimize costs across providers, and negotiate better rates for bulk usage.

Disclosure

Educational content only, not financial advice. API usage and crypto payments carry risks. Verify all transactions before signing. Do your own research.

Frequently Asked Questions

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About Token Metrics
Token Metrics: AI-powered crypto research and ratings platform. We help investors make smarter decisions with unbiased Token Metrics Ratings, on-chain analytics, and editor-curated “Top 10” guides. Our platform distills thousands of data points into clear scores, trends, and alerts you can act on.
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Token Metrics Team
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Recent Posts

Research

Indices Hub: Join the Waitlist for TM Global 100 (2025)

Token Metrics Team
5

If you’ve been waiting for a simple, rules-based way to own the Token Metrics Global 100—without micromanaging tokens—this hub is for you. The TM Global 100 is a rules-based crypto index that holds the top 100 assets in bull markets and moves to stablecoins in bear markets, with weekly rebalancing and transparent holdings/transaction logs you can verify at any time. It’s designed for hands-off allocators who want disciplined exposure and for active traders who want a core that adapts to regimes—without guesswork or endless rebalancing. Below you’ll find how it works, who it’s for, and exactly how to join the waitlist so you’re first in line when trading opens.

→ Join the waitlist to be first to trade TM Global 100.

Why Indices Matter in October 2025

Search intent right now: investors want credible, rules-based crypto exposure that can participate in upside while reducing drawdown pain. A crypto index is a basket of assets selected and maintained by rules—so you avoid one-off bets and constant manual rebalancing.

With liquidity rotating quickly across sectors, weekly rebalancing helps maintain alignment with current market-cap leaders, while regime switching provides a disciplined, pre-defined response to bearish conditions. The result is a clear, consistent process that removes emotional decision-making and operational drag.

Definition

A crypto index is a rules-based basket of digital assets that’s constructed, weighted, and rebalanced on a set schedule.

How the TM Global 100 Index Works (Plain English)

  • Regime switching: Bullish: Hold the top-100 crypto assets by market cap.
  • Bearish: Exit all positions into stablecoins and wait for a new bullish signal.
  • Weekly rebalancing: Reflects updated rankings and weights across the market-cap universe.
  • Transparency: Strategy modal shows methodology and thresholds; Gauge → Holdings Treemap → Transactions Log make every change visible.

What you’ll see on launch: Price tile, gauge (“rebalances weekly”), 100 tokens, one-click Buy Index flow, and a 90-second checkout via embedded wallet.‍See the strategy and rules.

Benefits at a Glance (Why This Beats DIY)

  • Time saved: No more manual coin-picking, sizing, and calendar rebalances.
  • Lower execution drag: One click vs. dozens of individual orders that can add slippage.
  • Stay current: Weekly rebalances help you capture market-cap changes without constant monitoring.
  • Discipline in drawdowns: Automatic switch to stablecoins removes panic decisions.
  • Radical visibility: Holdings treemap, table, and transactions log show what you own and what changed—every week.
  • Operational simplicity: Embedded wallet and a unified dashboard; no juggling chains and exchanges.

Step-by-Step: How to Get Early Access (Waitlist)

  1. Open the Indices Hub: Head to the Token Metrics Indices hub.
  2. Choose TM Global 100: Open the index page and review the Gauge → Strategy → Holdings.
  3. Join the Waitlist: Add your email to be notified the moment trading opens.
  4. (Optional) Connect Wallet: Pre-connect your wallet for a faster launch-day checkout.

Launch-Day Flow (~90 seconds): Tap Buy Index, review fees/slippage, confirm, and see your position in My Indices. Track Rebalances: After each weekly rebalance or regime change, check the Transactions Log for updates.

→ Join the waitlist to be first to trade TM Global 100.

Decision Guide: Is This Right for You?

  • Hands-Off Allocator: Want broad exposure without micromanaging? Yes—rules-based + weekly rebalances.
  • Active Trader: Need a core that sits in stables during bears while you hunt edges elsewhere? Fits.
  • TM Member/Prospect: Already trust Token Metrics research? This is the rules-based version of “own the market.”
  • Risk-Aware Newcomer: Prefer a clear framework over vibes? Methodology is visible and auditable.
  • DIY Basket Builder: Tired of missed rebalances and slippage? One click can reduce execution drag.
  • Data-First Analyst: Want to verify? See the holdings, weights, and transaction history anytime.

FAQs

1) What is a TM Global 100 index?

It’s a rules-based crypto index that holds the top 100 assets by market cap in bullish regimes and moves to stablecoins in bearish regimes. It rebalances weekly and shows transparent holdings and transactions.

2) How often does the index rebalance?

Weekly, with additional full-portfolio switches when the market regime changes.

3) What triggers the move to stablecoins?

A proprietary market signal. When bearish, the index exits all token positions into stablecoins and waits for a bullish re-entry signal.

4) Can I fund with USDC or fiat?

At launch, funding and settlement options surface based on the embedded wallet and supported chains. USDC payouts are supported for selling; additional entry options may be introduced later.

5) Is the wallet custodial?

No. The Embedded Wallet is self-custodial—you control your funds while using a streamlined, on-chain checkout.

6) How are fees shown?

Before you confirm, the Buy flow shows estimated gas, platform fee, maximum slippage, and the minimum expected value.

7) How do I join the waitlist?

Go to the Token Metrics Indices hub or the TM Global 100 strategy page and submit your email. We’ll notify you the moment trading opens.

Security, Risk & Transparency

  • Self-custody: Embedded smart wallet; you hold the keys.
  • 2FA & session hygiene: Use strong auth practices for your TM account.
  • Fee clarity: Gas, platform fee, and slippage are displayed before you confirm.
  • Auditability: Holdings, treemap, and transactions log are always visible.
  • Model limits: Regime logic can be wrong, and markets can gap; rules reduce discretion—not risk.
  • Regional availability: Product surfaces may vary by region as we expand.

Crypto is volatile and can lose value. Past performance is not indicative of future results. This article is for research/education, not financial advice.

Conclusion

If you want a disciplined, rules-based core that adapts to market regimes, Token Metrics Global 100 is built for you. Weekly rebalances, transparent holdings, and one-click buy remove operational friction so you can focus on your strategy.

→ Click here to get early access to Token Metrics indices.

Research

Top Crypto Index for Hands-Off Portfolios (2025)

Token Metrics Team
4

If you want broad exposure to cryptocurrencies without constant chart monitoring, a top crypto index offers a streamlined way to participate in the market. Token Metrics provides innovative tools to help you understand and access such indices efficiently.

Opening Hook

If you’re seeking an uncomplicated, rules-driven approach to crypto investing that adapts to market conditions, a top crypto index might be worth exploring. These indexes automate the process of capturing upside potential while managing risk during downturns, making crypto investing more accessible for a variety of investor profiles.

What is a Crypto Index?

A crypto index is a systematic, rules-based collection of digital assets that reflects a specific universe—such as the top 100 cryptocurrencies by market capitalization. It relies on transparent methodologies and scheduled rebalancing to ensure that the composition remains aligned with market dynamics. These indexes aim to provide broad exposure while reducing the need for individual asset management.

How Top Crypto Indexes Function in 2025

Many modern crypto indexes incorporate regime switching mechanisms: during bullish periods, they hold top assets; during bear markets, they shift to stablecoins to mitigate losses. Weekly rebalancing updates the constituents based on current market rankings, and transparency tools such as strategy descriptions, gauges, and transaction logs allow users to verify holdings and changes in real-time.

Benefits of Using a Crypto Index Over DIY Approaches

  • Time efficiency: Automates rebalancing and regime switching, saving manual effort.
  • Lower slippage: Executes large baskets with minimal impact on prices.
  • Consistency: Ensures regular rebalancing and discipline during volatile periods.
  • Transparency: Clear logs and dashboards allow for full accountability.
  • Speed: Simplified onboarding with quick allocation processes.

Getting Early Access to Top Crypto Indexes

To gain early exposure, follow these steps:

  1. Open the Token Metrics Indices hub.
  2. Select TM Global 100 and view its details.
  3. Tap “Join Waitlist” and enter your email (optionally connect your wallet).
  4. Review strategy criteria, holdings, and rebalancing rules.
  5. Once launched, connect your wallet, review estimated fees, and confirm your allocation.
  6. Funds appear in your index portfolio, enabling easy tracking and management.

Is This Index Suitable for You?

Consider your investment style:

  • Hands-Off Allocator: Ideal if you prefer broad market exposure with minimal management.
  • Active Trader: Use as a core component, complemented by higher-beta bets.
  • New to Crypto: Great for beginners seeking transparent exposure through simplified flows.
  • DIY Enthusiast: Replace complex basket-building with a rules-based index.
  • Self-Custody User: Benefit from integrated self-custodial wallets with clear transaction records.

FAQs

What is a top crypto index?

It is a rules-based basket that tracks a defined universe of digital assets—such as the top 100 by market cap—using transparent methodology and scheduled rebalancing.

How often does the index rebalance?

The index rebalances weekly, with regime switches occurring when market signals change, ensuring adaptability during different market cycles.

What prompts the move to stablecoins?

A proprietary market-regime signal triggers the transition, exiting token positions to stablecoins during bearish periods and re-entering when signals turn bullish.

Can I fund with USDC or fiat?

At launch, the embedded wallet will support supported funding options based on your chain or wallet. USDC payout is available upon sale; further options may follow.

Is the wallet custodial?

No. It’s an embedded, self-custodial smart wallet—giving you full control over your private keys and funds.

How are fees shown?

Estimated gas, platform fee, slippage, and minimum expected value are displayed before you confirm the transaction, providing full transparency.

How do I join the waitlist?

Visit the Token Metrics Indices hub or the TM Global 100 page, tap “Join Waitlist,” and follow the instructions to register your interest and prepare for launch.

Disclaimer

Crypto assets are highly volatile and can result in significant losses. Past performance does not guarantee future results. This content is for research and educational purposes only and not financial advice.

Research

Top 100 Crypto Index: What It Is, How It’s Built, and Who It’s For (2025)

Token Metrics Team
6

If you’ve tried to “own the market” in crypto, you’ve felt the pain: chasing listings, juggling wallets, and missing rebalances while prices move. A top 100 crypto index aims to fix that—giving you broad exposure when the market is bullish and standing down when it’s not. Token Metrics Global 100 is our rules-based version of that idea: it holds the top-100 by market cap in bull regimes, moves to stablecoins in bear regimes, and rebalances weekly. You can see every rule, every holding, and every rebalance—then buy the index in ~90 seconds with an embedded on-chain flow.‍ → Join the waitlist to be first to trade TM Global 100.

Why a “Top 100 Crypto Index” Matters in October 2025

The market keeps cycling. New leaders emerge quickly. A “set-and-forget” bag can fall behind, while manual baskets burn hours and rack up slippage. Search interest for crypto index, regime switching, and weekly rebalancing keeps growing because people want a simple, disciplined core that adapts.

A top 100 crypto index is a rules-based basket that tracks the largest 100 crypto assets by market cap, typically rebalanced on a schedule to keep weights aligned with the market. In 2025, that alone isn’t enough. You also need discipline for downtrends. Token Metrics adds a regime-switching layer to move to stablecoins during bear phases—so you can participate in upside and sit out major drawdowns with a consistent, rules-based approach.

How the TM Global 100 Index Works (Plain English)

Regime switching:

  • Bullish: The index holds the top-100 assets by market cap.
  • Bearish: The index exits positions and moves fully to stablecoins until a bullish re-entry signal.

Weekly rebalancing:

  • Every week, the composition and weights update to reflect current market-cap rankings. No manual list maintenance. No “oops, I missed the new entrant.”

Transparency:

  • Strategy modal explains selection criteria and regime logic.
  • Gauge → Treemap → Transactions Log shows the signal, the real-time holdings view, and every rebalance/regime switch.

You’ll always see what you own, how it changed, and why.

What you’ll see on launch

  • Price tile, 100 tokens, “rebalances weekly,” and one-click Buy.
  • Gauge to visualize the market signal.
  • Holdings Treemap and Table to inspect exposure.
  • Transactions Log to review every rebalance.
  • See the strategy and rules.

Benefits at a Glance (Why This Beats DIY)

  • Time saved: Skip hours of asset chasing and manual spreadsheets; rebalances happen automatically.
  • Lower execution drag: One index buy can reduce slippage vs. piecing together 20–50 small orders across chains.
  • Never miss a rebalance: Weekly updates and on/off risk switches run by rules, not vibes.
  • Rules-based switching: A clear trigger defines when to sit in stablecoins—no second-guessing.
  • Full visibility: The gauge, treemap, table, and log make the process auditable at a glance.
  • Operational simplicity: An embedded wallet, 90-second buy flow, fee and slippage estimates upfront.

Step-by-Step: How to Get Early Access (Waitlist)

  1. Open the Indices hub and tap TM Global 100.
  2. Join the waitlist with your email—this flags you for day-one access.
  3. (Optional) Connect your wallet so you’re ready for the embedded checkout.
  4. Launch day: You’ll get an email and in-app prompt when trading opens.
  5. Buy in ~90 seconds: Connect, review fees/slippage/estimated value, confirm.
  6. Track positions: See your holdings, rebalances, and P&L in My Indices.
  7. Repeat or add funds: Rebalancing is handled weekly; you can add or sell anytime.

→ Join the waitlist to be first to trade TM Global 100.

Decision Guide: Is This Right for You?

  • Hands-Off Allocator: Want broad market exposure without managing coin lists? Consider it.
  • Active Trader: Want a disciplined core you don’t have to watch while you chase setups? Consider it.
  • TM Member (Research-Heavy): Prefer to keep your picks, but want a market base layer? Consider it.
  • New to Crypto: Need transparency + clear rules? Consider it, with a small test first.
  • Hyper-Niche Maxi: If you only want 1–2 coins, an index may be too broad.
  • Short-Term Scalper: You may still benefit from a core allocation, but active trading stays your main driver.
  • Tax-/Jurisdiction-Sensitive Users: Check your local rules before investing.
  • Institutional Explorers: Looking for transparent rules, logs, and weekly governance? Worth evaluating.

FAQs

What is a top 100 crypto index?

A rules-based basket tracking the largest 100 assets by market cap, typically with scheduled rebalancing. Token Metrics Global 100 adds regime switching to stablecoins during bear markets.

How often does the index rebalance?

Weekly. In addition, if the market signal flips, the entire portfolio may switch between tokens ↔ stablecoins outside the weekly cycle.

What triggers the move to stablecoins?

A proprietary market-regime signal. When it’s bearish, the index exits tokens to stablecoins and waits for a bullish re-entry signal.

Can I fund with USDC or fiat?

On launch, funding options surface based on your connected wallet and supported chains. USDC payouts are supported when selling.

Is the wallet custodial?

The embedded wallet is self-custodial—you control your funds.

How are fees shown?

Before you confirm a buy, you’ll see estimated gas, platform fee, max slippage, and minimum expected value—all up front.

How do I join the waitlist?

Go to the TM Global 100 page or the Indices hub and click Join Waitlist. You’ll get notified at launch with simple steps to buy.

Security, Risk & Transparency

  • Self-custody: Embedded, self-custodial smart wallet; you control keys.
  • 2FA & device checks: Standard authentication best practices.
  • Fee/slippage transparency: All estimates are shown pre-trade; you confirm with eyes open.
  • On-chain visibility: Holdings, rebalances, and regime switches appear in the Transactions Log.
  • Rule constraints: Signals can be wrong; spreads and volatility can impact outcomes.
  • Regional considerations: Availability and tax treatment vary by jurisdiction.

Crypto is volatile and can lose value. Past performance is not indicative of future results. This article is for research/education, not financial advice.

A top 100 crypto index is the simplest path to broad market exposure—if it’s built with discipline. Token Metrics Global 100 combines transparent rules, weekly rebalancing, and a regime switch to stablecoins, so you can focus on your strategy while the core maintains itself. Now’s the time to claim early access.‍ → Join the waitlist to be first to trade TM Global 100.

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