Add docs for constraint-dependencies and override-dependencies (#6596)

Add missing portions of documents reported in #6518 and #5248(Comment).

## Summary

<img width="600" alt="override"
src="https://github.com/user-attachments/assets/062f0036-8672-4c68-b21c-aebdeb79b58b">

<img width="600" alt="constraint"
src="https://github.com/user-attachments/assets/f5ef1aa2-0662-4352-a1a0-3af1127fb7fb">

crates/uv-settings/src/settings.rs

@@ -40,13 +40,9 @@ pub struct Options {
     pub top_level: ResolverInstallerOptions,
     #[option_group]
     pub pip: Option<PipOptions>,
-    #[cfg_attr(
-        feature = "schemars",
-        schemars(
-            with = "Option<Vec<String>>",
-            description = "PEP 508 style requirements, e.g. `ruff==0.5.0`, or `ruff @ https://...`."
-        )
-    )]
+
+    // NOTE(charlie): These fields are shared with `ToolUv` in
+    // `crates/uv-workspace/src/pyproject.rs`, and the documentation lives on that struct.
     pub override_dependencies: Option<Vec<Requirement<VerbatimParsedUrl>>>,
     pub constraint_dependencies: Option<Vec<Requirement<VerbatimParsedUrl>>>,
 

crates/uv-workspace/src/pyproject.rs

@@ -137,14 +137,66 @@ pub struct ToolUv {
         "#
     )]
     pub environments: Option<SupportedEnvironments>,
+    /// Overrides to apply when resolving the project's dependencies.
+    ///
+    /// Overrides are used to force selection of a specific version of a package, regardless of the
+    /// version requested by any other package, and regardless of whether choosing that version
+    /// would typically constitute an invalid resolution.
+    ///
+    /// While constraints are _additive_, in that they're combined with the requirements of the
+    /// constituent packages, overrides are _absolute_, in that they completely replace the
+    /// requirements of any constituent packages.
+    ///
+    /// !!! note
+    ///     In `uv lock`, `uv sync`, and `uv run`, uv will only read `override-dependencies` from
+    ///     the `pyproject.toml` at the workspace root, and will ignore any declarations in other
+    ///     workspace members or `uv.toml` files.
     #[cfg_attr(
         feature = "schemars",
         schemars(
             with = "Option<Vec<String>>",
-            description = "PEP 508-style requirements, e.g. `ruff==0.5.0`, or `ruff @ https://...`."
+            description = "PEP 508-style requirements, e.g., `ruff==0.5.0`, or `ruff @ https://...`."
         )
     )]
+    #[option(
+        default = r#"[]"#,
+        value_type = "list[str]",
+        example = r#"
+            # Always install Werkzeug 2.3.0, regardless of whether transitive dependencies request
+            # a different version.
+            override-dependencies = ["werkzeug==2.3.0"]
+        "#
+    )]
     pub override_dependencies: Option<Vec<pep508_rs::Requirement<VerbatimParsedUrl>>>,
+    /// Constraints to apply when resolving the project's dependencies.
+    ///
+    /// Constraints are used to restrict the versions of dependencies that are selected during
+    /// resolution.
+    ///
+    /// Including a package as a constraint will _not_ trigger installation of the package on its
+    /// own; instead, the package must be requested elsewhere in the project's first-party or
+    /// transitive dependencies.
+    ///
+    /// !!! note
+    ///     In `uv lock`, `uv sync`, and `uv run`, uv will only read `constraint-dependencies` from
+    ///     the `pyproject.toml` at the workspace root, and will ignore any declarations in other
+    ///     workspace members or `uv.toml` files.
+    #[cfg_attr(
+        feature = "schemars",
+        schemars(
+            with = "Option<Vec<String>>",
+            description = "PEP 508-style requirements, e.g., `ruff==0.5.0`, or `ruff @ https://...`."
+        )
+    )]
+    #[option(
+        default = r#"[]"#,
+        value_type = "list[str]",
+        example = r#"
+            # Ensure that the grpcio version is always less than 1.65, if it's requested by a
+            # transitive dependency.
+            constraint-dependencies = ["grpcio<1.65"]
+        "#
+    )]
     pub constraint_dependencies: Option<Vec<pep508_rs::Requirement<VerbatimParsedUrl>>>,
 }
 

docs/reference/settings.md

@@ -168,6 +168,47 @@ specified as `KEY=VALUE` pairs.
 
 ---
 
+#### [`constraint-dependencies`](#constraint-dependencies) {: #constraint-dependencies }
+
+Constraints to apply when resolving the project's dependencies.
+
+Constraints are used to restrict the versions of dependencies that are selected during
+resolution.
+
+Including a package as a constraint will _not_ trigger installation of the package on its
+own; instead, the package must be requested elsewhere in the project's first-party or
+transitive dependencies.
+
+!!! note
+    In `uv lock`, `uv sync`, and `uv run`, uv will only read `constraint-dependencies` from
+    the `pyproject.toml` at the workspace root, and will ignore any declarations in other
+    workspace members or `uv.toml` files.
+
+**Default value**: `[]`
+
+**Type**: `list[str]`
+
+**Example usage**:
+
+=== "pyproject.toml"
+
+    ```toml
+    [tool.uv]
+    # Ensure that the grpcio version is always less than 1.65, if it's requested by a
+    # transitive dependency.
+    constraint-dependencies = ["grpcio<1.65"]
+    ```
+=== "uv.toml"
+
+    ```toml
+    
+    # Ensure that the grpcio version is always less than 1.65, if it's requested by a
+    # transitive dependency.
+    constraint-dependencies = ["grpcio<1.65"]
+    ```
+
+---
+
 #### [`dev-dependencies`](#dev-dependencies) {: #dev-dependencies }
 
 The project's development dependencies. Development dependencies will be installed by
@@ -772,6 +813,48 @@ Disable network access, relying only on locally cached data and locally availabl
 
 ---
 
+#### [`override-dependencies`](#override-dependencies) {: #override-dependencies }
+
+Overrides to apply when resolving the project's dependencies.
+
+Overrides are used to force selection of a specific version of a package, regardless of the
+version requested by any other package, and regardless of whether choosing that version
+would typically constitute an invalid resolution.
+
+While constraints are _additive_, in that they're combined with the requirements of the
+constituent packages, overrides are _absolute_, in that they completely replace the
+requirements of any constituent packages.
+
+!!! note
+    In `uv lock`, `uv sync`, and `uv run`, uv will only read `override-dependencies` from
+    the `pyproject.toml` at the workspace root, and will ignore any declarations in other
+    workspace members or `uv.toml` files.
+
+**Default value**: `[]`
+
+**Type**: `list[str]`
+
+**Example usage**:
+
+=== "pyproject.toml"
+
+    ```toml
+    [tool.uv]
+    # Always install Werkzeug 2.3.0, regardless of whether transitive dependencies request
+    # a different version.
+    override-dependencies = ["werkzeug==2.3.0"]
+    ```
+=== "uv.toml"
+
+    ```toml
+    
+    # Always install Werkzeug 2.3.0, regardless of whether transitive dependencies request
+    # a different version.
+    override-dependencies = ["werkzeug==2.3.0"]
+    ```
+
+---
+
 #### [`prerelease`](#prerelease) {: #prerelease }
 
 The strategy to use when considering pre-release versions.

uv.schema.json

@@ -57,12 +57,13 @@
       ]
     },
     "constraint-dependencies": {
+      "description": "PEP 508-style requirements, e.g., `ruff==0.5.0`, or `ruff @ https://...`.",
       "type": [
         "array",
         "null"
       ],
       "items": {
-        "$ref": "#/definitions/Requirement"
+        "type": "string"
       }
     },
     "dev-dependencies": {
@@ -254,7 +255,7 @@
       ]
     },
     "override-dependencies": {
-      "description": "PEP 508-style requirements, e.g. `ruff==0.5.0`, or `ruff @ https://...`.",
+      "description": "PEP 508-style requirements, e.g., `ruff==0.5.0`, or `ruff @ https://...`.",
       "type": [
         "array",
         "null"