How Zed handles this
You are in Zed with the agent panel open next to a theme, and mobile visitors see a layout that the desktop version of a page does not. You ask whether xSpeed keeps one cached copy for every device. The agent calls list_sites, then list_modules and get_settings for the cache module, and reads whether a separate mobile cache is on. It answers from the real value on that site instead of from general knowledge about caching.
What comes back is an answer and an offer: the separate mobile cache is off, so phones and desktops share one stored copy. That matters only when shop sends different HTML by device, such as AMP or a mobile theme, so the agent asks before it suggests a change; a responsive theme needs the default. The Hub tells the agent to briefly confirm intent before update_settings, so the agent says what it will change and waits for you. After your yes it calls update_settings and shows the stored value. If any key or value is wrong, the whole call is refused and nothing is stored, Pro-only modules are refused on a site without a licence, and credential fields are refused over the Hub.
What differs in Zed is how often you are asked. Zed's default tool permission is confirm, which prompts for every tool call, reads included, so a short audit with list_modules and several get_settings calls means several approvals before any write. That is a good default for settings changes, because the Hub runs a write as soon as your connection allows it. If the repeated prompts on reads bother you, give each read tool its own allow entry, such as mcp:xspeedhub:get_settings, and keep confirm for update_settings and toggle_cache.
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.
Using xSpeed Hub, does shop keep a separate cached copy for mobile visitors? Read the cache settings and tell me.
Use xSpeed Hub to turn on the separate mobile cache on shop and show me the setting before and after.
Ask xSpeed Hub for the modules on blog and tell me which ones have a setting that affects mobile visitors.
What happens, step by step
Every xSpeed feature is a module with its own settings. Through xSpeed Hub an agent can list the modules a site has, read one module's settings, change them with a checked update, and turn page caching on or off. The site validates every write against the module's own schema, so a wrong key or value is refused with a reason instead of being quietly ignored.
01
List the modules
list_modules returns every Free and Pro module available on one site, with its settings schema and status. It tells the agent which module slugs exist, such as minify or gzip, and what each setting accepts.
02
Read the current settings
get_settings takes a module slug and returns its settings. Credential fields come back masked, so an agent cannot read a stored API token or password back in plain text.
03
Change them
update_settings takes the module and a values object of setting keys. The site checks the whole object first. If any key is unknown, any value is outside the schema, or a field is pinned by a constant in wp-config.php, it refuses the write, writes nothing and says which keys and why, sometimes with a "did you mean" hint.
04
Turn page caching on or off
Page caching has its own tool, toggle_cache, because it installs or removes the cache drop-in and the WP_CACHE constant. Asking update_settings to set cache_enabled does not work and is refused. If another caching plugin owns the drop-in, the site declines to enable xSpeed and returns blocked: true with the reason.
05
Check the effect
The result of a settings write is the stored settings. A module can add a warning when a setting is saved but has no effect on this server, for example Brotli on a server without the module for it, and the agent should pass that on. run_benchmark then times cached against uncached to see whether the change helped.
06
Apply to many sites only after reading one
update_settings and toggle_cache accept site: "all" or a list of handles. Each site validates against its own schema and answers in its own row, so a module missing on one site fails that row and the others still apply. Read one site first, then apply.
Reference
| Discover | list_modules (read): Free and Pro modules, settings schema, status, per site |
|---|---|
| Read settings | get_settings (read): argument module; credential fields masked |
| Change settings | update_settings (write): arguments module and values; validated by the site |
| Bad input | The whole write is refused and nothing is written; the error names the keys and reasons |
| Page cache on or off | toggle_cache (write): argument enabled; cache_enabled in update_settings is refused |
| Blocked by another plugin | toggle_cache returns blocked: true with blocked_reason when another plugin owns the cache drop-in |
| Every site at once | update_settings and toggle_cache accept site: "all" or a list of handles, one result per site |
| Pro modules | A Pro module on a site without an active licence cannot be read or written; the site refuses |
| Credential fields | Refused by default over MCP; set them in the xSpeed dashboard, not through the agent |
| Read-only connection | The connection token with Read-only everywhere on, or a Viewer member's sign-in: update_settings and toggle_cache are refused; list_modules and get_settings still work. An OAuth sign-in gets the scopes the client asks for, read and write by default, clamped to the member's role |
| Confirmation | None on the Hub; the Hub tells the agent to briefly confirm intent for these two, and your client's prompt is the gate |
Rules worth keeping
- Read before you write. Ask for list_modules and get_settings first, so the agent changes real keys with valid values instead of guessing.
- update_settings and toggle_cache change how a live site behaves. They run as soon as your connection allows writes. The Hub tells the agent to briefly confirm intent first, which is guidance to the agent, so your client's approval prompt and a read-only connection (the connection token with Read-only everywhere on, or a Viewer sign-in) are the gates. The switch does not limit an OAuth sign-in.
- For site: "all", the Hub tells the agent to confirm once with "this will touch all N sites", then make one call. The result is per site, and some sites failing is a partial result to report, not a blanket success or failure.
- Do not ask an agent to set credentials such as a Cloudflare token or Redis password. The site refuses those writes by default, and they belong in the xSpeed dashboard.
- If a settings result says a value is saved but inactive on this server, relay that. Do not tell the user the feature is enabled.
Good to know with Zed
Zed asks before every tool call by default, including reads, so tuning settings takes more clicks than in clients that prompt only for writes. Do not clear that by setting the global default to allow, which auto-approves every tool. Zed documents per-tool entries for MCP tools but no wildcard, so allow list_modules and get_settings one by one, and keep confirm on update_settings and toggle_cache. If the panel never asks, the default has been changed, and the Hub will then run the write at once.
More prompts for this job
They work in any client connected to xSpeed Hub.
Use xSpeed Hub to list the modules on shop and tell me which ones are off.
Ask xSpeed Hub for the current minify settings on blog.
With xSpeed Hub, turn on HTML minification on blog, then benchmark the cache and tell me if it helped.
Use xSpeed Hub to turn page caching off on staging while I debug, and tell me when it is off.
Using xSpeed Hub, read the gzip settings on shop first, then enable the same options on every site.
Use xSpeed Hub to set the page cache lifespan on docs to 30 days, and if the site refuses it, tell me why.
Frequently asked questions
Keep going
Tune cache settings with other agents
More with Zed
Documentation
- How to enable Page Cache
- How to minify CSS and JavaScript
- How to add cache rules and bypasses
- Site MCP tool reference
- How to write prompts for xSpeed Hub
- Zed + xSpeed
- Every AI agent that works with xSpeed
From the blog