diff --git a/src/libfetchers/fetchers.cc b/src/libfetchers/fetchers.cc
index c54c39cf0..000609f09 100644
--- a/src/libfetchers/fetchers.cc
+++ b/src/libfetchers/fetchers.cc
@@ -89,11 +89,6 @@ Attrs Input::toAttrs() const
     return attrs;
 }
 
-bool Input::hasAllInfo() const
-{
-    return getNarHash() && scheme && scheme->hasAllInfo(*this);
-}
-
 bool Input::operator ==(const Input & other) const
 {
     return attrs == other.attrs;
@@ -117,7 +112,7 @@ std::pair<Tree, Input> Input::fetch(ref<Store> store) const
     /* The tree may already be in the Nix store, or it could be
        substituted (which is often faster than fetching from the
        original source). So check that. */
-    if (hasAllInfo()) {
+    if (getNarHash()) {
         try {
             auto storePath = computeStorePath(*store);
 
@@ -175,8 +170,6 @@ std::pair<Tree, Input> Input::fetch(ref<Store> store) const
 
     input.locked = true;
 
-    assert(input.hasAllInfo());
-
     return {std::move(tree), input};
 }
 
diff --git a/src/libfetchers/fetchers.hh b/src/libfetchers/fetchers.hh
index b55aabb6f..f52175e41 100644
--- a/src/libfetchers/fetchers.hh
+++ b/src/libfetchers/fetchers.hh
@@ -79,15 +79,6 @@ public:
      */
     bool isLocked() const { return locked; }
 
-    /**
-     * Check whether the input carries all necessary info required
-     * for cache insertion and substitution.
-     * These fields are used to uniquely identify cached trees
-     * within the "tarball TTL" window without necessarily
-     * indicating that the input's origin is unchanged.
-     */
-    bool hasAllInfo() const;
-
     bool operator ==(const Input & other) const;
 
     bool contains(const Input & other) const;
@@ -144,8 +135,6 @@ struct InputScheme
 
     virtual ParsedURL toURL(const Input & input) const;
 
-    virtual bool hasAllInfo(const Input & input) const = 0;
-
     virtual Input applyOverrides(
         const Input & input,
         std::optional<std::string> ref,
diff --git a/src/libfetchers/git.cc b/src/libfetchers/git.cc
index c1a6dce43..26b8987d6 100644
--- a/src/libfetchers/git.cc
+++ b/src/libfetchers/git.cc
@@ -321,15 +321,6 @@ struct GitInputScheme : InputScheme
         return url;
     }
 
-    bool hasAllInfo(const Input & input) const override
-    {
-        bool maybeDirty = !input.getRef();
-        bool shallow = maybeGetBoolAttr(input.attrs, "shallow").value_or(false);
-        return
-            maybeGetIntAttr(input.attrs, "lastModified")
-            && (shallow || maybeDirty || maybeGetIntAttr(input.attrs, "revCount"));
-    }
-
     Input applyOverrides(
         const Input & input,
         std::optional<std::string> ref,
diff --git a/src/libfetchers/github.cc b/src/libfetchers/github.cc
index d7450defe..b824140a6 100644
--- a/src/libfetchers/github.cc
+++ b/src/libfetchers/github.cc
@@ -132,11 +132,6 @@ struct GitArchiveInputScheme : InputScheme
         };
     }
 
-    bool hasAllInfo(const Input & input) const override
-    {
-        return input.getRev() && maybeGetIntAttr(input.attrs, "lastModified");
-    }
-
     Input applyOverrides(
         const Input & _input,
         std::optional<std::string> ref,
diff --git a/src/libfetchers/indirect.cc b/src/libfetchers/indirect.cc
index e09d8bfb8..947849802 100644
--- a/src/libfetchers/indirect.cc
+++ b/src/libfetchers/indirect.cc
@@ -78,11 +78,6 @@ struct IndirectInputScheme : InputScheme
         return url;
     }
 
-    bool hasAllInfo(const Input & input) const override
-    {
-        return false;
-    }
-
     Input applyOverrides(
         const Input & _input,
         std::optional<std::string> ref,
diff --git a/src/libfetchers/mercurial.cc b/src/libfetchers/mercurial.cc
index b0d2d1909..f830a3271 100644
--- a/src/libfetchers/mercurial.cc
+++ b/src/libfetchers/mercurial.cc
@@ -98,13 +98,6 @@ struct MercurialInputScheme : InputScheme
         return url;
     }
 
-    bool hasAllInfo(const Input & input) const override
-    {
-        // FIXME: ugly, need to distinguish between dirty and clean
-        // default trees.
-        return input.getRef() == "default" || maybeGetIntAttr(input.attrs, "revCount");
-    }
-
     Input applyOverrides(
         const Input & input,
         std::optional<std::string> ref,
diff --git a/src/libfetchers/path.cc b/src/libfetchers/path.cc
index 092975f5d..d829609b5 100644
--- a/src/libfetchers/path.cc
+++ b/src/libfetchers/path.cc
@@ -66,11 +66,6 @@ struct PathInputScheme : InputScheme
         };
     }
 
-    bool hasAllInfo(const Input & input) const override
-    {
-        return true;
-    }
-
     std::optional<Path> getSourcePath(const Input & input) override
     {
         return getStrAttr(input.attrs, "path");
diff --git a/src/libfetchers/tarball.cc b/src/libfetchers/tarball.cc
index 269a56526..ba47d59a7 100644
--- a/src/libfetchers/tarball.cc
+++ b/src/libfetchers/tarball.cc
@@ -253,12 +253,6 @@ struct CurlInputScheme : InputScheme
             url.query.insert_or_assign("narHash", narHash->to_string(HashFormat::SRI, true));
         return url;
     }
-
-    bool hasAllInfo(const Input & input) const override
-    {
-        return true;
-    }
-
 };
 
 struct FileInputScheme : CurlInputScheme