How Zed handles this
You checked the site while signed in to WordPress, opened developer tools, and every request says BYPASS. Cached pages are never served to logged-in users, which makes this the most common false alarm. You ask in the Agent Panel: caching looks dead on blog, check before I change anything.
The agent reads get_cache_status and run_benchmark. Caching is on, the hit ratio is 71% and the benchmark's cached request is a hit. Nothing is wrong. It tells you to test in a private window or with a plain GET request, because xSpeed never caches a logged-in request, and you have saved yourself a settings change. If the numbers had been bad, it would read get_health next and name the failing check.
Zed's default for agent tool permissions is to confirm, and it applies to every call, reads included. A diagnosis of two or three calls is two or three prompts. You can loosen it for the read tools alone with a per-tool entry such as mcp:xspeedhub:get_health set to allow, or with the Always for tool button in the prompt. Zed documents no wildcard for MCP tools, so each read tool gets its own entry, and everything else stays on confirm. The Agent Panel keeps the answer beside your code, so it is easy to ask a follow-up in the same thread: how do I test this properly next time? The usual answer is a private window, or a request from a shell with no cookies. It is worth saving as a note for the next person who sees BYPASS and assumes caching broke.
Set up Zed once
Already connected? Skip to the prompts. Alternatives and troubleshooting are on the Zed guide.
1Put your sites in xSpeed Hub
Sign in at app.xspeedcache.com with Google or email; the Hub is free and has no site cap. Then connect each WordPress site from its own dashboard: click Connect Hub in the xSpeed Cache top bar, then Connect via xSpeed Hub. Each site needs the free xSpeed Cache plugin.
2Add xSpeed Hub as a remote server
Open Settings, then AI, then MCP Servers, click Add Server and choose Add Remote Server. Or run zed: open settings file and add the entry yourself. Zed calls MCP servers context servers, so the key is context_servers.
{
"context_servers": {
"xspeedhub": {
"url": "https://app.xspeedcache.com/xspeed/mcp"
}
}
} 3Sign in
Because the entry has no Authorization header, Zed prompts you to authenticate against the server with the standard MCP OAuth flow. Approve access on the xSpeed Hub page that opens. There is no token to paste. Back in Settings, AI, MCP Servers, a green dot beside xspeedhub with the tooltip Server is active means it is connected.
Settings → AI → MCP Servers
Full Zed setup, sign-in options and FAQ
Before you send a prompt that changes something
Reads change nothing on your sites, though contact_support emails xSpeed support. Writes run once your connection allows them, so your client's approval prompt and a read-only connection (the token's Read-only everywhere switch, or a Viewer sign-in) are the gates that matter. The Zed agent confirms before it runs any tool action. The default setting, agent.tool_permissions.default, is confirm, and that covers MCP tool calls, reads included. A per-tool entry such as mcp:xspeedhub:get_cache_status with a default of allow lets that one tool run without a prompt, and the Always for tool button in the prompt writes the same entry. Setting the global default to allow auto-approves every tool, writes included, and then a write reaches the Hub as soon as your connection allows writes. xSpeed Hub has no confirmation step of its own.
What do I ask?
Three prompts written for Zed. More for this job are below.
I see BYPASS on blog in developer tools. Use xSpeed Hub to check the cache status and the benchmark and tell me whether caching is actually working.
Using xSpeed Hub, was my BYPASS caused by being logged in? Explain it, and tell me how to test properly.
With xSpeed Hub, run the benchmark on blog and tell me whether the cached request was a hit.
What happens, step by step
When a WordPress page is not served from cache, the cause is usually one of a few things: caching is off, the cache drop-in or the WP_CACHE constant is missing, another caching plugin is in the way, or the pages carry something that makes them uncacheable. Through xSpeed Hub an agent can read the cache status, run the site's full health diagnostics, time a cached request against an uncached one, and check which Pro features would help, all without changing anything.
01
Start with the quick summary
get_cache_status returns whether page caching is on, the stats (cached pages, size, hit ratio, last purge) and the web server xSpeed detected. It is a glance. If caching is off, or the hit ratio is far below what you expect, the agent moves on to the diagnostic.
02
Run the diagnostic
get_health is the tool for troubleshooting. It returns the environment checks with pass or warn tones (the advanced-cache.php drop-in, the WP_CACHE constant, rewrite rules, PHP and WordPress versions, caching plugin conflicts), the cache stats, 24 hourly hit and miss buckets and a 30-day hit-ratio series. The Hub tells the agent to use it, not get_cache_status, when you are troubleshooting rather than glancing.
03
Time cached against uncached
run_benchmark requests the home page once with the cache bypassed and once normally, after a warm-up request, and returns the timings. If the second request still is not a cache hit, the page cache is not serving the home page, and the result says so. It measures xSpeed's own response time. It does not return a Lighthouse score.
04
Read what the checks mean
A warn is a lead, not always a fault. A static-file rewrite warning, for example, can mean the nginx snippet is not in your server config yet, or that xSpeed could not verify it, which is not evidence the config is wrong. The agent reads the detail line and tells you which one it is.
05
Fix it or hand it over
If caching is simply off, toggle_cache turns it on. If another caching plugin owns the drop-in, the site refuses to enable xSpeed and says why; removing the other plugin is yours to do. If nothing explains it, contact_support emails xSpeed support with the agent's summary, after the agent has confirmed the message with you.
Reference
| Quick check | get_cache_status (read): cache on or off, stats, detected web server |
|---|---|
| Diagnostic | get_health (read): environment checks, 24 hourly buckets, 30-day hit-ratio series, recent activity |
| One site per call | get_health does not accept site: "all"; call it for each site you care about |
| Benchmark | run_benchmark (read): home page only, cache bypassed against cache served, timings in milliseconds |
| Benchmark on every site | run_benchmark accepts site: "all" or a list of handles, one result per site |
| Benchmark history | get_benchmark_history reads past runs and the settings changes on the same timeline |
| Pro suggestions | get_pro_audit (read): which Pro features would help this site, from its settings and stats |
| Hit ratio scope | Counts requests that reach your server; pages answered by a CDN or Cloudflare edge are not counted |
| Support | contact_support emails xSpeed support with your account email and site list attached; classed read |
| Turning caching on | toggle_cache (write); refused by the site when another plugin owns the cache drop-in |
Rules worth keeping
- Diagnose with the read tools first. get_cache_status, get_health, run_benchmark and get_pro_audit change nothing on the site, so a read-only connection can run all of them. For clients that send the connection token, that means Read-only everywhere on; an OAuth sign-in gets the scopes the client asks for, unless the member is a Viewer.
- Do not answer a PageSpeed question with run_benchmark. It measures cached against uncached response time and returns no Lighthouse score; for a score, use the speed test or scan jobs.
- toggle_cache is a write. It runs as soon as your connection allows writes, and the Hub tells the agent to confirm the target site first. That is guidance to the agent, so your client's approval prompt is the gate that matters.
- contact_support sends a real email. The Hub tells the agent to confirm the message with you before sending, but the tool is classed read, so even a read-only connection can send one.
- The agent cannot edit your server configuration or another plugin's settings. When a check needs an nginx snippet or a conflicting plugin removed, it tells you what to do and you do it.
Good to know with Zed
Because Zed confirms every call by default, you are well covered on writes, but it also teaches you to click through. Keep the rule loose for the read tools and leave toggle_cache, update_settings, purge_cache and contact_support on confirm. Setting the global default to allow auto-approves every tool, writes included. The Hub does not ask again: it only tells the agent to confirm the target site and the message. And read the prompt for contact_support, because it sends mail.
More prompts for this job
They work in any client connected to xSpeed Hub.
Using xSpeed Hub, why is the cache hit ratio so low on shop? Run the full health check and tell me the most likely cause.
Using xSpeed Hub, is page caching actually working on blog? Benchmark cached against uncached and tell me if the second request was a hit.
xSpeed Hub's get_health on docs shows a warning about the static-file rewrite. What does it mean and do I need to act?
Use xSpeed Hub to check whether another caching plugin is conflicting with xSpeed on shop.
Caching looks off on the staging site. Use xSpeed Hub to turn it on and tell me if the site refuses.
Using xSpeed Hub, which Pro features would help the shop site, based on how it is set up now?
With xSpeed Hub, compare the last few benchmark runs on blog and tell me whether my settings changes helped.
Frequently asked questions
Keep going
Find out why pages are not cached with other agents
More with Zed
Documentation
- How to read your cache diagnostics
- Understanding cache hits and misses
- How to check your site health
- Common problems and troubleshooting
- How to enable Page Cache
- How to write prompts for xSpeed Hub
- Zed + xSpeed
- Every AI agent that works with xSpeed
From the blog