How Gemini CLI handles this
You are in Gemini CLI and you have a sensible rule for how long pages should stay cached, but your sites have drifted: one has 6 hours, another 48, and a third has the default. You ask Gemini CLI to set the cache expiry to 24 hours everywhere. It calls list_sites to count them, then get_settings on a couple of sites to see what the values look like, and tells you what update_settings would write before it sends anything.
What comes back is a plan and a single question. The Hub tells the agent to confirm once before a write that touches every site, in words like this will touch all 6 sites, and Gemini CLI asks you. After your yes it sends one update_settings call with site: "all". The Hub runs the sites one after another with a one-second pause and returns a result for each, so one site that is unreachable shows as a failed row while the others are stored. Each site validates against its own schema, credential fields are refused over the Hub, and a Pro-only setting is refused where there is no licence.
What differs in Gemini CLI is the trust setting. By default it shows a confirmation for an MCP tool call, with the choices to proceed once, always allow that tool, always allow the whole server, or cancel. That is the check you want for a write across a fleet. If the server entry sets trust to true, you chose always allow, or you started Gemini CLI with --approval-mode=yolo (or --yolo), which approves every tool call, it stops asking, and a fleet-wide update_settings then runs the moment the model decides to send it. The Hub has no confirmation of its own, so do not trust xspeedhub if you plan to use this job.
Set up Gemini CLI once
Already connected? Skip to the prompts. Alternatives and troubleshooting are on the Gemini CLI 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 Gemini CLI
Run this once. --scope user writes the server to ~/.gemini/settings.json so it works in every project; without it Gemini CLI saves to the project's .gemini/settings.json, which is the default.
gemini mcp add --scope user --transport http xspeedhub https://app.xspeedcache.com/xspeed/mcp
3Authenticate with /mcp auth
Start gemini and run /mcp auth xspeedhub. A browser page opens where you sign in to xSpeed Hub and approve access, and Gemini CLI receives the redirect on a local port. There is no token to paste, and the client keeps the credentials it receives. Run /mcp afterwards to check that xspeedhub shows as connected and lists its tools.
/mcp auth xspeedhub
Full Gemini CLI 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. Gemini CLI shows a confirmation for an MCP tool call unless the server entry sets trust to true or you start Gemini CLI with --approval-mode=yolo (or --yolo), which approves every tool call. You can proceed once, always allow that tool, always allow the whole xspeedhub server, or cancel; the last two choices stop later prompts for those tools. Policy rules in ~/.gemini/policies can allow, deny or ask for a named tool by server and tool name. The Hub has no confirmation step of its own, so a trusted server, YOLO mode or an allow rule lets a write run as soon as your connection allows writes.
What do I ask?
Three prompts written for Gemini CLI. More for this job are below.
Use xSpeed Hub to set the page cache expiry to 24 hours on every site, but read the current value on each first and show me which ones differ.
Using xSpeed Hub, which of my sites do not have the cache module on? Read only, change nothing.
With xSpeed Hub, apply the same lazy loading settings I use on shop to blog and docs, and show me the per-site result.
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 Gemini CLI
Gemini CLI asks before a tool call unless the server is set as trusted, you chose always allow for the tool or the server, or you started it with --approval-mode=yolo (or --yolo), which approves every tool call. After that, a settings write across every site runs with no prompt from the client, and the Hub's request to confirm becomes the only check. Leave trust off and do not add --trust to this server. A policy rule in your Gemini CLI policies can ask or deny update_settings by name, and a read-only connection (the connection token with Read-only everywhere on, or a Viewer sign-in) makes the write tools refuse.
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 Gemini CLI
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
- Gemini CLI + xSpeed
- Every AI agent that works with xSpeed
From the blog