How Grok handles this
You are in a Grok chat on grok.com with xSpeed Hub added as a custom connector, and two of your sites feel different for no clear reason: blog loads lean, while docs feels heavy on every page. You ask Grok to compare them. Because the question is about your sites, Grok reaches for the connector. It calls get_settings for the minify module on both sites, and list_modules if it needs to see what else is switched on, so the comparison rests on stored values rather than on general advice about WordPress speed.
What comes back is the gap, stated plainly: blog minifies its CSS and JavaScript and docs does neither. Grok proposes the smallest change that closes it, turning on CSS and JavaScript minify on docs and leaving defer off until you have tested it, and the Hub tells the agent to briefly confirm intent before update_settings. After your yes it calls update_settings for docs and shows the stored values. The site checks every key and value against the module schema, so a wrong one refuses the whole call and nothing is written, a Pro-only module is refused on a site without a licence, and credential fields are refused over the Hub. A warning that a setting is saved but has no effect on that server should be passed on, not dropped.
What differs in Grok is the approval model. xAI's connector documentation describes no per-tool approval setting, and it says Grok can use a connector's tools whenever your question relates to that service. So the question Grok asks in the chat is the only pause before update_settings or toggle_cache, and it comes from the model's habit and the Hub's instructions, not from a switch you set. Word requests with care: say read only when you only want a comparison, and read what Grok says it is about to change before you answer yes.
Set up Grok once
Already connected? Skip to the prompts. Alternatives and troubleshooting are on the Grok 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 custom connector
Go to grok.com/connectors, click New Connector and select Custom. Enter this as the MCP server URL and complete the authentication: approve access on the xSpeed Hub page that opens. Grok then reads the Hub's tools and makes them available in your conversations.
https://app.xspeedcache.com/xspeed/mcp
3Ask a first question
Start a chat and ask something that names xSpeed Hub, so Grok reaches for the connector. A list of your sites with their cache status means the connection works.
Use xSpeed Hub to list my sites and tell me which ones have page caching turned off.
Full Grok 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. xAI's connector documentation describes no per-tool approval setting. It says Grok can use a connector's tools whenever your questions relate to that service. xSpeed Hub has no confirmation step of its own, so a purge or a settings change runs as soon as Grok calls it and your connection allows writes. The Hub tells the agent to confirm the target site and to ask once before a write that touches every site, but that is an instruction, not a lock. If you want Grok to read and never change anything, sign in as a Viewer member of the workspace, which only ever gets read access. Otherwise read what Grok says it is about to do before you answer yes.
What do I ask?
Three prompts written for Grok. More for this job are below.
Using xSpeed Hub, compare the minify settings on blog and docs and tell me what differs. Read only.
With xSpeed Hub, turn on CSS and JavaScript minify on docs, and show me the settings before and after.
Ask xSpeed Hub which modules are off on shop and explain what each one would do if I turned it on.
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 Grok
If you want Grok to look and never write, sign in to xSpeed Hub as a Viewer member of the workspace, which only ever gets read access, so the Hub refuses update_settings and toggle_cache whatever Grok decides. The connection token's Read-only everywhere switch does not help here, because xAI describes no header field for a custom connector and the sign-in is OAuth. On Grok Business and Enterprise a team admin has to provision the connector in the cloud console before you can add it.
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 Grok
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
- Grok + xSpeed
- Every AI agent that works with xSpeed
From the blog