Z.ai GLM-5.1 API Slow or Failing?
Clash Rules for Zhipu Domains and Node Routing

1. GLM-5.1, Z.ai, and BigModel in 2026

The narrative around GLM-5.1 is not only about benchmark slides; it is about long-horizon agents that keep sockets open across tool calls, file edits, and multi-step builds. Whether you pull weights locally or call hosted inference, the hosted path still matters for day-to-day engineering: official SDKs distinguish a Mainland China base URL rooted at open.bigmodel.cn and an overseas base at api.z.ai, both speaking the same Paas-style REST layout under /api/paas/v4/. That split is intentional—latency, compliance, and peering differ—but it also means your Clash profile must know which hostname your laptop actually hits. A team that standardized on the Z.ai key flow but left YAML tuned only for openai.com will see mysterious half-working setups: the marketing page loads while completion streams reset, or the reverse happens when documentation assets resolve differently from API hosts.

Zhipu (智谱) branding often appears beside BigModel.cn documentation, billing, and console flows, while Z.ai carries the international console and developer docs. Product marketing can move faster than your static rule list, so treat any table in this article as a baseline rather than scripture. Capture fresh hostnames from DevTools or mitmproxy whenever a client update ships, then collapse them to DOMAIN-SUFFIX rows you can audit in Git. The operational goal is simple: every TLS ClientHello whose SNI ends with the vendor apex you care about should match a predictable outbound before your generic GEOIP bucket or terminal MATCH fires.

If proxy-groups, rules, and resolver modes are unfamiliar, start with the configuration overview. For comparing desktop UIs that expose per-connection logs, see Clash Verge vs. Clash for Windows—readable logs matter when you correlate browser console traffic with SDK calls from the same machine.

2. Symptoms: Console vs API Paths

Operators frequently compress failures into “the model is down,” yet the engineering timeline forks once you read Clash connection logs. The public Z.ai web experience may pull HTML from z.ai while background fetches hit api.z.ai for completions, usage telemetry, or feature flags. A YAML file that only lists the apex marketing host leaves API subrequests on DIRECT or on a noisy default pool, which produces intermittent spinners and mid-stream GOAWAY frames that feel like rate limits but are really transport instability. On the BigModel side, the documented entry for many keys remains https://open.bigmodel.cn/api/paas/v4/; SDKs append paths such as chat/completions to that host. Because Clash matches SNI rather than REST paths inside TLS, hostname coverage is the correct abstraction: once open.bigmodel.cn rides your intended outbound, future path tweaks stay covered until the vendor changes the hostname itself.

Transport-class failures—TLS handshake stalls, abrupt TCP resets after switching Wi-Fi, or HTTP/2 ping timeouts—usually trace to unstable egress, MTU issues, or multiplexing quirks, not to a missing toggle inside the vendor console. Application-class failures—clean HTTP 401, crisp 429 JSON bodies citing quota, or structured billing errors—mean credentials, plan limits, or abuse defenses; rewriting split routing will not refill an exhausted wallet. Learning that distinction saves weekends: either you refine rules and node selection, or you open a ticket with receipts from the vendor dashboard. This article stays strictly on the networking side for readers who already have legitimate access.

Long GLM-5.1 agent sessions amplify the difference. Coding agents may open parallel HTTPS connections for repository metadata, tool responses, and streaming deltas. If the first hop uses a stable Singapore node but a follow-up asset resolves through a domestic path because of a mis-ordered GEOIP rule, the client sees “random” slowdowns that no single refresh fixes. Treat agent traffic like microservices traffic: every dependency hostname must be intentional.

3. Domains Zhipu and Z.ai Use

Official SDK READMEs emphasize two base URLs: https://api.z.ai/api/paas/v4/ for overseas accounts and https://open.bigmodel.cn/api/paas/v4/ for Mainland China accounts. Documentation portals typically live on docs.z.ai and docs.bigmodel.cn, while account or subscription flows may bounce across additional first-party subdomains under the same apex names. The sustainable workflow—identical in spirit to our DeepSeek guide—is to export failing URLs from DevTools, collapse them to suffixes, and insert fresh DOMAIN-SUFFIX rows above broad catch-alls. Avoid importing anonymous “AI mega packs” that interleave unrelated vendors; they create false confidence while leaking critical SNI strings to DIRECT.

Real browsers still pull auxiliary requests: analytics, static bundles, identity handoffs, and occasional third-party CDNs. Those names rotate with releases. Use the table below as a starting point, then extend it with whatever your own captures show after each SDK upgrade.

Refreshing the list safely

Whenever marketing ships a new onboarding experiment, diff freshly captured hostnames against the Git-managed snippet your team imports through rule-providers. If identity flows hop through an unrelated IdP domain, follow corporate policy for that traffic—but do not assume the IdP replaces explicit coverage for api.z.ai itself. TLS inspection appliances can mimic proxy failures; confirm with IT before discarding an otherwise sound profile.

4. Boundaries: LAN, Mirrors, and API

Split routing is powerful because it is selective; indiscriminate tunneling creates new outages. Corporate intranet resources, internal artifact registries, and on-prem Git remotes should usually remain on DIRECT or a dedicated corporate outbound that your security team approves. Place explicit IP-CIDR or DOMAIN-SUFFIX rows for those zones above your Zhipu rules so a broad DOMAIN-SUFFIX,z.ai matcher cannot accidentally steal traffic meant for a private registry hostname that happens to include marketing keywords in its path. The same discipline applies to npm, PyPI, and apt mirrors: if your workplace mandates a domestic mirror for speed, routing those downloads through a foreign retail node because of a sloppy keyword rule wastes bandwidth and triggers compliance alarms.

Our npm and git terminal proxy guide focuses on environment variables such as HTTPS_PROXY so CLI tools honor your local mixed port. That work is complementary, not redundant: even perfect shell exports will not fix a browser session whose api.z.ai connections never hit Clash because system proxy exclusions or split DNS misaligned with TUN. Think in layers—terminal env for stubborn binaries, Clash rules for HTTPS SNI from browsers and language runtimes that respect the OS proxy, and optional TUN when processes ignore both.

Finally, remember that HTTP API stability is a function of keep-alive behavior, HTTP/2 window sizes, and how aggressively your node selection policy flaps between regions. Package downloads are bursty large objects; model streams are long skinny JSON lines. The outbound that excels at one workload may jitter on the other.

5. Why ChatGPT Lists Do Not Help

Companion posts for ChatGPT / OpenAI, Gemini, and Claude share the same choreography—ordered rules, dedicated groups, resolver alignment—but the hostname sets are not interchangeable. openai.com will never terminate traffic meant for api.z.ai; bigmodel.cn shares no suffix with those Western stacks. Importing a recycled “AI bundle” without verification is how engineers end up with impressive YAML that still leaks a critical GLM-5.1 call to DIRECT.

Routing “all foreign HTTPS” through one catch-all sometimes hides the gap until a chatty UI opens parallel connections for uploads, citations, and incremental tokens. A dedicated PROXY-ZHIPU tag makes regressions honest: when only Z.ai degrades after a subscription rotates peers, you know exactly which pool to benchmark. It also keeps audit narratives crisp—reviewers can read the suffix list you export without wading through unrelated domains.

Avoid lazy DOMAIN-KEYWORD,glm matchers unless you are actively tailing logs. Keywords false-positive on unrelated blogs and false-negative when teams adopt neutral CDN hostnames. Prefer suffix rules anchored to apex names you have actually observed, then widen deliberately.

6. Split Routing Order in Clash

Rule-based split routing keeps domestic SaaS on fast local paths while steering selected HTTPS flows through remote outbounds. Zhipu sessions are chatty: the interface may open parallel fetches for account state, uploads, and streaming answer tokens. If the first request hits PROXY-ZHIPU but a follow-up asset still matches a broad GEOIP rule that sends traffic DIRECT, users perceive random “stuck at ninety percent” behavior that no single refresh fixes. Clash evaluates rules top to bottom; the first match wins. Place your z.ai and bigmodel.cn suffix rows above any catch-all foreign bucket or terminal MATCH so they cannot be skipped after a subscription merge reorders lines.

Mode matters as much as ordering. System-proxy users sometimes forget that stubborn binaries ignore OS settings; TUN adopters must confirm the virtual interface captures the processes they care about. Regardless of mode, DNS must agree with how rules resolve names. Fake-IP, redir-host, and custom nameserver-policy blocks can produce answers that differ from what dig prints on the host. When those pipelines diverge, you chase phantoms: the browser thinks it is talking to one address while the core maps another SNI string to a stale fake mapping. Re-read the DNS and mode documentation whenever you toggle TUN, inject DoH upstreams, or import a third-party profile that redefines dns.

For generative workloads, headline throughput is misleading. A stable node that keeps you in the same metro for the entire coding session usually outperforms a peer that flaps every health check and forces the client to rebuild cookies, HTTP/2 state, and vendor-side rate buckets. Design groups around stability first, then optimize latency.

7. Example Rules (YAML Patterns)

The snippets below communicate intent, not a drop-in subscription. Rename outbounds, verify compatibility with your core (Mihomo, Meta, etc.), and never import anonymous rule packs without auditing them—hostile YAML can forward traffic to attacker-controlled peers.

Create a narrow group so unrelated url-test churn does not steal your AI egress:

proxy-groups:
  - name: PROXY-ZHIPU
    type: url-test
    proxies:
      - node-sgp-01
      - node-jp-01
      - node-us-west-01
    url: https://www.gstatic.com/generate_204
    interval: 300
    tolerance: 80

Pin international Z.ai traffic ahead of generic foreign pools. A single suffix covers api.z.ai, docs.z.ai, and most console subdomains unless compliance forces child-zone splits:

rules:
  - DOMAIN-SUFFIX,z.ai,PROXY-ZHIPU
  # Mainland BigModel stack (omit or change outbound if policy forbids foreign exit)
  - DOMAIN-SUFFIX,bigmodel.cn,PROXY-ZHIPU
  # Optional corporate branding / SSO you observed in captures:
  # - DOMAIN-SUFFIX,zhipuai.cn,PROXY-ZHIPU
  # ... your intranet DIRECT rules should appear above this block ...
  - MATCH,FINAL

Teams that manage many laptops often publish these rows through a rule-providers URL so operations can hotfix hostname gaps without rebuilding entire profiles. If regulations require isolating API traffic on a datacenter-only outbound, duplicate specific DOMAIN matchers above the broader suffix entry—but expect to revisit the list whenever gateways rotate.

8. Node Selection for Agents

Nodes that win short probes may still collapse when a browser opens many parallel HTTPS connections for uploads, tool calls, and incremental answer tokens. For node selection, pair url-test with a generous tolerance so the group does not yo-yo between regions whenever latency jitters—nothing triggers mystery session banners faster than continent hopping mid-stream. When you need deterministic ordering, wrap the same peers inside a fallback group and measure which upstream survives a five-minute heavy session with real tool traffic, not just synthetic pings.

Multiplexing (smux, gRPC options, etc.) occasionally interacts poorly with HTTP/2 streaming. If bodies truncate right before the model finishes, test with multiplexing disabled, then re-enable once you identify the culprit. Experimental QUIC paths in Chromium can bypass the TCP assumptions you made while debugging; temporarily disabling QUIC is a valid isolation step, not a permanent lifestyle. Corporate networks sometimes force specific regions or block UDP outright; validate those constraints before you spend nights tuning Clash.

Isolate Zhipu traffic from a noisy default pool

If your generic “Foreign” group mixes residential, datacenter, and bulk-download peers, carve Z.ai and BigModel into PROXY-ZHIPU so unrelated traffic cannot starve interactive latency. The YAML cost is trivial; the observability win is enormous when only GLM-5.1 degrades after an upstream maintenance window.

9. DNS, Fake-IP, and Rate Buckets

DNS is the hidden coupling between your browser, your operating system, and the proxy core. When Clash resolves api.z.ai through its internal stack but Chrome still uses a system resolver that points at an ISP recursor, you can pass SNI checks yet still observe bizarre hangs: the page shell loads from cache while live fetches miss. Start every serious debugging session by listing which resolver owns each interface—Ethernet, Wi-Fi, VPN adapters, and the TUN device—and whether secure DNS is enabled inside the browser independently of the OS. If you terminate DoH inside the browser to a public provider while the core uses fake-ip mapping, expect intermittent divergence until you either disable the browser’s secure DNS for testing or align it with the same policy table your YAML exports.

Operators who forward DNS queries through the same outbound as their web traffic usually get the most predictable results. That might mean sending Clash’s upstream nameserver connections through PROXY-ZHIPU or a sibling group, or using proxy-server-nameserver style settings when your core supports them. The opposite failure mode—forcing DoH straight to a resolver hosted in a region your corporate firewall blocks—looks identical to a “Z.ai outage” even though the service is healthy. Document the tuple that works: which nameserver you used, whether fake-ip is on, and which outbound tag those queries followed.

Fake-IP remains invaluable for split routing, yet it demands discipline. Stale mappings after you switch Wi-Fi networks or suspend a laptop can send traffic to the wrong interface until you flush state or restart the core. IPv6 introduces another fork: if some answers prefer AAAA records while your tunnel only handles IPv4 paths, you will see hangs that disappear when you temporarily disable IPv6 or route it consistently. Browser extensions that ship their own DNS or proxy logic can double-wrap sessions; reproduce bugs with a clean profile before you file upstream tickets.

Finally, account safety systems correlate IP, ASN, and timing. Rapid hopping caused by hyperactive url-test groups can trigger step-up challenges that resemble geo blocks. Keep a steady egress long enough to finish OAuth, then optimize. Vendor-side API throttling during peak windows can also surface as HTTP 429; read dashboard notices before you blame the tunnel.

10. Self-Check Checklist

Before you blame Zhipu for an outage, walk through this sequence:

1. Confirm rule hits. In connection logs, verify z.ai and bigmodel.cn hosts show PROXY-ZHIPU (or your tag), not stray DIRECT lines hiding below a mis-ordered MATCH.
2. Compare resolvers. Compare dig api.z.ai on the host with the answer inside Clash’s DNS inspector. Mismatches imply fake-ip or DoH drift.
3. Test TLS manually. Run curl -I https://api.z.ai and curl -I https://open.bigmodel.cn through your mixed or HTTP inbound port—timeouts usually mean transport, while crisp HTTP status codes point to application semantics.
4. Read API errors literally. Structured JSON errors typically cite quota or key issues; chasing YAML in those cases wastes time.
5. Strip extensions and double VPNs. One proxy at a time keeps the signal clean.

Archive the working profile revision in Git whenever you change DNS or nodes. Future you will thank present you after the next macOS or Windows update rewires resolver precedence.

11. Availability and Terms

Changing routes alters how remote services perceive your network path; it does not waive Zhipu or Z.ai terms, workplace acceptable-use policies, export controls, or local regulations. Use AI products only where you are entitled to do so, respect regional availability, and treat this article as operational guidance rather than legal counsel.

We do not document evading fraud prevention, abuse mitigations, payment verification, or access controls. If a challenge screen appears for legitimate risk reasons, work through official support flows. Our scope stays strictly on transparent Clash configuration for readers who already hold valid accounts. Open-source repositories remain valuable for auditing the client ecosystem; still, install signed builds from the official distribution channel linked below instead of random mirrors.

12. Summary

Reliable GLM-5.1 access in 2026 hinges on naming the right infrastructure: at minimum DOMAIN-SUFFIX,z.ai for the international console and api.z.ai stack, plus DOMAIN-SUFFIX,bigmodel.cn when your keys target open.bigmodel.cn, augmented with any zhipuai.cn or CDN suffixes your captures reveal. Order those rules ahead of broad catch-alls, pair the list with a dedicated outbound, tune node selection for long-lived HTTP/2 streams instead of vanity speed tests, and keep DNS behavior aligned with whichever mode—TUN, system proxy, or mixed port—you actually run. Separate this work mentally from npm mirror tuning: both matter, but they solve different layers of the stack.

Compared with opaque one-tap VPN apps, Clash shines when teams treat routing as version-controlled infrastructure: logs tell the truth, profiles diff cleanly, and you can prove which domains left which path during an incident review. A maintained client with transparent updates makes that workflow sustainable; grabbing builds from a trusted channel matters as much as YAML hygiene.

Grab installers from this site’s download page whenever you onboard a new machine—then layer the Zhipu-focused rules on top of a baseline you can reproduce.

→ Download Clash for free and experience the difference