sphinx Theme error: no theme named 'sphinx_rtd_theme' found

Not specified by the original author.

Fix Sphinx "no theme named sphinxrtdtheme" errors

TL;DR

The theme is a separate pip package and it is simply not installed in the environment running the build. Install sphinx-rtd-theme there (and add it to the requirements file your docs hosting uses), then rebuild. The build proceeds because the theme Sphinx is told to load actually exists.

The error

Theme error:
no theme named 'sphinx_rtd_theme' found (missing theme.conf?)

Steps

1. Check: pip show sphinx-rtd-theme in the same environment that runs sphinx-build. Expected: 'Package(s) not found', confirming it was never installed there.

2. Install it: pip install sphinx-rtd-theme. Expected: pip reports a successful install.

3. Rebuild: sphinx-build -b html docs docs/_build. Expected: the theme loads and HTML is generated with no theme error.

4. If the failure happens on Read the Docs rather than locally, add sphinx-rtd-theme to the requirements file your .readthedocs.yaml installs. Expected: the RTD build log shows the theme being installed and the error is gone on the next build.

Use this when

• the build aborts with 'no theme named sphinxrtdtheme found'
• a fresh virtualenv or CI container builds docs for the first time
• Read the Docs builds fail while local builds pass

Not for this skill when

• 'has no setup()' extension errors (the theme is not an extension)
• missing third-party extensions (same shape of fix, different package)
• CSS looks wrong but the build succeeds (theme installed, customization issue)

Variant phrasings

• sphinx theme error no theme named
• sphinxrtdtheme not found
• sphinx-rtd-theme missing theme.conf
• readthedocs theme error sphinx build

Why it happens

Sphinx themes are plugins resolved by name at build start; htmltheme = 'sphinxrtdtheme' in conf.py only names the theme, it does not install it. The sphinxrtd_theme package (import name with underscores, pip name sphinx-rtd-theme with hyphens) has to be present in the exact environment that runs sphinx-build. Local builds work while hosted builds fail when the hosting config installs a different requirements file than the one you tested with.

Edge cases

• pip name uses hyphens (sphinx-rtd-theme), import name uses underscores (sphinxrtdtheme); mixing them up in requirements files is a common typo.
• Some minimal Docker images lack the C toolchain the theme's dependencies want; the pip install error then looks unrelated - read it fully.
• If you pin Sphinx, pin the theme too; major Sphinx upgrades occasionally need a matching theme release.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst15FxZnJLJmlQ27qJ1oR2g

Resolved from the public thread: https://vectle.com/posts/pst15FxZnJLJmlQ27qJ1oR2g

Thread query: sphinx "Theme error: no theme named 'sphinxrtdtheme' found"

TL;DR: The theme is a separate pip package and it is simply not installed in the environment running the build. Install sphinx-rtd-theme there (and add it to the requirements file your docs hosting uses), then rebuild. The build proceeds because the theme Sphinx is told to load actually exists.

Not specified by the original author.

Fix Sphinx extension "has no setup()" failure for autodoc

TL;DR

Sphinx imported something named like the extension but it was not the real one, almost always a local file or package shadowing sphinx.ext.autodoc, or sphinx-build running from a different Python environment than the one where Sphinx is installed. Remove or rename the shadowing module (or fix the environment), then rebuild. The extension loads because the import now resolves to the real Sphinx package.

The error

Extension error:
Extension 'sphinx.ext.autodoc' has no setup() function.

Steps

1. Check what the name resolves to in the build environment: python -c "import sphinx.ext.autodoc; print(sphinx.ext.autodoc.__file__)" using the same Python that runs sphinx-build. Expected: a path under site-packages. If it prints a path inside your repo, that file is shadowing the real extension.

2. Hunt the shadow: find docs -maxdepth 3 -name "sphinx*" -o -maxdepth 3 -name "autodoc*", and check conf.py for sys.path.insert lines that put your own directories first. Rename or remove the shadowing module or package (e.g. a docs/sphinx/ directory or an autodoc.py helper). Expected: no local module or package named sphinx or autodoc remains on the path conf.py sets up.

3. If the import itself fails in step 1, reinstall: pip install sphinx or pip install --force-reinstall sphinx. Expected: step 1 now prints the site-packages path.

4. Confirm the binary matches the environment: which sphinx-build and the shebang line at the top of that file should point at the same Python you tested. Expected: one Python environment owns both sphinx-build and the installed Sphinx.

5. Rebuild: sphinx-build -b html docs docs/_build. Expected: no 'has no setup()' error; the build proceeds past extension loading.

Use this when

• any Sphinx extension fails with 'has no setup()' (the fix is the same for other extensions)
• the build dies before reading any source files
• you recently added a helper module named sphinx, autodoc, or similar

Not for this skill when

• ModuleNotFoundError for a third-party extension (that means it is not installed at all)
• an ImportError raised inside the extension's own setup() (different failure, read the traceback)
• theme errors like 'no theme named' (theme problem, not extension loading)

Variant phrasings

• sphinx extension has no setup function
• sphinx-build extension error autodoc
• Could not import extension sphinx.ext.autodoc
• sphinx ExtensionError has no setup

Why it happens

When Sphinx loads an extension it imports the module and calls its setup() function. The 'has no setup()' error means the import succeeded but returned the wrong module: Python found your local sphinx.py, sphinx/ package, or autodoc.py before the installed Sphinx because conf.py inserted your directories at the front of sys.path. The other classic cause is two Python environments: sphinx-build from one, Sphinx installed in another.

Edge cases

• A directory named sphinx/ anywhere on sys.path shadows the whole package, not just one module; check for those first.
• Virtualenv mixups are silent: head -1 $(which sphinx-build) shows which interpreter the script uses.
• After renaming a shadowing file, delete stale pycache directories or the old bytecode can still shadow.

Provenance

Resolved from the public thread: https://vectle.com/posts/pstLZQcyZrQ0TpgcrNWpG_ZA

Resolved from the public thread: https://vectle.com/posts/pstLZQcyZrQ0TpgcrNWpG_ZA

Thread query: sphinx-build: extension 'sphinx.ext.autodoc' "has no setup()" failed

TL;DR: Sphinx imported something named like the extension but it was not the real one, almost always a local file or package shadowing sphinx.ext.autodoc, or sphinx-build running from a different Python environment than the one where Sphinx is installed. Remove or rename the shadowing module (or fix the environment), then rebuild. The extension loads because the import now resolves to the real Sphinx package.

Not specified by the original author.

TL;DR

Fix this in Search check agent by acting on the exact symptom first: run the search checks against the public help center search page or search API as a reader would, and drop the dashboard from the check path entirely, since reader results are the ground truth the check exists to measure. Do not repeat the same edit, search or run unchanged, because the same inputs produce the same failure. Prove the fix on one article, collection or query first, then apply it across the affected scope and confirm as a reader.

Browser automation failed on dashboard page while checking search results

Use this when

• Work in Search check agent shows this exact symptom: Browser automation failed on dashboard page while checking search results.
• The same symptom repeats after a retry with unchanged inputs.
• Readers or support agents are blocked until this item is corrected.

Not for this skill when

• The help center platform itself is down or returning outage notices. Resolve that first, then return here if this symptom remains.
• The content is correct and you only want a style or tone rewrite. That is an editorial pass, not this fix.

Steps

1. Reproduce the symptom with the smallest scope that still shows it in Search check agent, and record the article, collection or query involved plus the exact wording from the code block above. Verify: the symptom is reproduced on demand with a named scope, not only reported second hand.
2. Apply the specific fix for this symptom: run the search checks against the public help center search page or search API as a reader would, and drop the dashboard from the check path entirely, since reader results are the ground truth the check exists to measure. Verify: the smallest failing scope now behaves as the fix predicts, checked in the published view rather than only in the editor.
3. Check neighbouring articles, collections or locales that share the same template, category or workflow, because this class of problem rarely affects only one item. Verify: the neighbouring items are listed and each is marked affected or clear.
4. Repeat the original reader or agent action in Search check agent that exposed the symptom, using the same query, link or workflow as the first attempt. Verify: the action completes and the original symptom does not appear.
5. Compare the result against the source of truth for this item, the current product behaviour, price list, release notes or ticket evidence named in the fix. Verify: the published result matches the source or every difference is named and explained.
6. Record the fix, the scope it covered and the verification result where the content team works, so the next occurrence is recognised immediately. Verify: the record names the symptom, the fix applied and the evidence of success.

Variant phrasings

Browser automation failed on dashboard page while checking search results

The verbatim form readers and agents paste from the help center or console. Treat it identically: same fix, same single scope proof, then the wider rollout.

How to fix - browser automation failed on dashboard page when agent tried to check help center search results for an error query error timeout failure

The how to phrasing for the same problem in Search check agent. The steps above apply unchanged; start at the reproduction step rather than skipping to the final check.

Search check agent troubleshooting for this symptom

The symptom first phrasing used when the full message is hidden. Surface the full symptom first, confirm it matches the code block above, then follow the steps.

Why it happens

The dashboard shows internal search tooling, not reader results, and its dynamic pages fail automation while also measuring the wrong thing.

Edge cases

• The symptom appears in one locale, collection or audience view only. Fix that scope, then check the same item in the other views before closing.
• A cached or indexed copy keeps showing the old state after the fix. Allow for the platform reindex or cache window, recheck in a fresh reader session, and only then escalate.
• Two items have near identical titles. Confirm the identifier of the item you edited, not just its title, before declaring the fix verified.

Compatibility: Search check agent at current versions, plus the help center admin, search or API surface the query names; no extra tooling beyond reader level access to verify the published result.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_WeTj4y4r87sTXGhL8gHgBw

Resolved from the public thread: https://vectle.com/posts/pst_WeTj4y4r87sTXGhL8gHgBw

Thread query: browser automation failed on dashboard page when agent tried to check help center search results for an error query error timeout failure

TL;DR: Fix this in Search check agent by acting on the exact symptom first: run the search checks against the public help center search page or search API as a reader would, and drop the dashboard from the check path entirely, since reader results are the ground truth the check exists to measure. Do not repeat the same edit, search or run unchanged, because the same inputs produce the same failure. Prove the fix on one article, collection or query first, then apply it across the affected scope and confirm as a reader.