How Kiro handles this
You expected the fastest cache path and the response time says otherwise: about 85 ms, not a handful. You are in Kiro with the site's code open, and you ask: pages on shop hit the cache but feel slower than they should, why? It reads get_cache_status first, to confirm that caching is on and the hit ratio is healthy.
Then it reads get_health and runs run_benchmark. Caching works, and the benchmark's cached request is a hit. The health report says hits are served through PHP because the pages contain nonces. A statically served file runs no PHP, so it could never refresh a nonce, and xSpeed serves those pages through PHP on purpose. The answer is that nothing is broken and no server snippet will change it. Without nonces, a static route would be a server configuration step.
Kiro prompts before it runs an MCP tool unless the tool is on the server's autoApprove list or a permission rule allows it. That makes it easy to approve exactly the read tools this job needs and nothing else. Ask Kiro to say what would have to change for a static file to be served, and what that would cost. It turns a vague worry about speed into a decision: keep the nonce pages as they are, or change them. The first needs no work, and the second is a change to your site that you would make yourself, outside xSpeed.
Set up Kiro once
Already connected? Skip to the prompts. Alternatives and troubleshooting are on the Kiro 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 to mcp.json
Open the command palette and run Kiro: Open user MCP config (JSON), then add this entry. The user file applies in every workspace. A project can carry its own .kiro/settings/mcp.json instead, but Kiro does not load a workspace's MCP config until you trust that workspace. Kiro reconnects servers when you save the file.
{
"mcpServers": {
"xspeedhub": {
"url": "https://app.xspeedcache.com/xspeed/mcp"
}
}
} 3Approve access in the browser
After you save, Kiro opens the xSpeed Hub authorization page. It registers itself through dynamic client registration, so there is no client ID to create. Sign in to the Hub, approve, and check the MCP servers tab in the Kiro panel for a connected xspeedhub. There is no token to paste; Kiro keeps the credentials it receives.
Full Kiro 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. Kiro prompts before it runs an MCP tool unless a rule allows it. Rules live in two places: autoApprove in the server's mcp.json entry, which lists tool names, and mcp rules in permissions.yaml, such as a match of xspeedhub/get_* with effect allow. Allow the reads and keep purge_cache, update_settings, toggle_cache and the other write tools off both lists, because the Hub itself runs a write as soon as your connection allows it. Putting "*" in autoApprove skips the prompt for every Hub tool, writes included. In a workspace you have not trusted, Kiro asks before every MCP call even when autoApprove lists the tool.
What do I ask?
Three prompts written for Kiro. More for this job are below.
Cached pages on shop take about 85 ms. Check the xSpeed Hub health report and tell me why they are not served faster.
Using xSpeed Hub, is the nginx static rewrite active on shop? Read the health checks and tell me.
Ask xSpeed Hub for a benchmark on shop and explain 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 Kiro
If you add tools to autoApprove, add get_cache_status, get_health, run_benchmark and get_pro_audit by name and stop there. Leave contact_support and the write tools off the list. The Hub has no confirmation step of its own: a write runs as soon as your connection allows it, and its request that the agent confirm first is guidance to the model. An entry in autoApprove removes the one prompt you would otherwise have seen, and an asterisk there skips the prompt for every Hub tool, writes included. In a workspace you have not trusted, Kiro asks before every MCP call even when autoApprove lists the tool. For a report-only setup, list the write tools and contact_support in disabledTools so Kiro never offers them to the agent.
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 Kiro
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
- Kiro + xSpeed
- Every AI agent that works with xSpeed
From the blog