diff --git a/packages/cli-engine/package.json b/packages/cli-engine/package.json
index 35b995b5..c839f45f 100644
--- a/packages/cli-engine/package.json
+++ b/packages/cli-engine/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@prisma/cli-engine",
-  "version": "0.4.0",
+  "version": "0.5.0",
   "description": "The execution engine of the unified Prisma CLI.",
   "type": "module",
   "exports": {
diff --git a/packages/cli-engine/src/commands.ts b/packages/cli-engine/src/commands.ts
index a5fc412e..5fc54b77 100644
--- a/packages/cli-engine/src/commands.ts
+++ b/packages/cli-engine/src/commands.ts
@@ -401,6 +401,8 @@ export interface ServerCommandDefinition<
       readonly cwd: string;
       readonly env: Readonly<Record<string, string | undefined>>;
       readonly config: TConfig;
+      /** The config file the run read, absolute; see CommandContext. */
+      readonly configFile: string | null;
     },
   ) => Promise<number>;
 }
diff --git a/packages/cli-engine/src/context.ts b/packages/cli-engine/src/context.ts
index 554dfdd6..ba4926f2 100644
--- a/packages/cli-engine/src/context.ts
+++ b/packages/cli-engine/src/context.ts
@@ -110,6 +110,16 @@ export interface CommandContext<
   /** Where the user invoked the CLI. Handlers never read process.cwd(). */
   readonly cwd: string;
 
+  /**
+   * The config file this run read, absolute: the one `--config` named,
+   * resolved against cwd, otherwise the prisma.config.ts discovered in
+   * cwd. A relative path inside the file is relative to the file, so a
+   * handler anchors such paths on this file's directory, never on cwd —
+   * the two differ whenever `--config` points into another directory.
+   * Null for a command with no config need, which never reads the file.
+   */
+  readonly configFile: string | null;
+
   /**
    * The invocation's environment, from Runtime.env. Handlers read env
    * via ctx.env, never process.env.
diff --git a/packages/cli-engine/src/execution/command-context.ts b/packages/cli-engine/src/execution/command-context.ts
index bac5f6df..704c1d60 100644
--- a/packages/cli-engine/src/execution/command-context.ts
+++ b/packages/cli-engine/src/execution/command-context.ts
@@ -123,6 +123,7 @@ export function makeContext(
   invocation: Invocation,
   def: AnyCommand,
   config: unknown,
+  configFile: string | null,
   capabilities: CommandCapabilities,
 ): CommandContext<unknown, number> {
   const state = invocation.state;
@@ -164,6 +165,7 @@ export function makeContext(
   let api: ManagementApiClient | undefined;
   const context: CommandContext<unknown, number> = {
     config,
+    configFile,
     present: present as CommandContext<unknown, number>["present"],
     activeCredential: (): Promise<ActiveCredential | null> =>
       invocation.runtime.credentialManager?.activeCredential() ??
diff --git a/packages/cli-engine/src/execution/engine.ts b/packages/cli-engine/src/execution/engine.ts
index 2bed1cc6..cdf1e12a 100644
--- a/packages/cli-engine/src/execution/engine.ts
+++ b/packages/cli-engine/src/execution/engine.ts
@@ -275,6 +275,7 @@ type ErasedServerHandler = (
     readonly cwd: string;
     readonly env: Readonly<Record<string, string | undefined>>;
     readonly config: unknown;
+    readonly configFile: string | null;
   },
 ) => Promise<number>;
 
@@ -660,6 +661,7 @@ export class EngineImpl implements Engine {
       invocation,
       entry.def,
       needsOutcome.config,
+      needsOutcome.configFile,
       declaredCapabilities(entry.def),
     );
     if (entry.def.kind === "session-command") {
@@ -744,6 +746,7 @@ export class EngineImpl implements Engine {
         cwd: runtime.cwd,
         env: runtime.env,
         config: needsOutcome.config,
+        configFile: needsOutcome.configFile,
       });
       if (!Number.isInteger(exitCode) || exitCode < 0 || exitCode > 255) {
         settleBug(
diff --git a/packages/cli-engine/src/execution/needs.ts b/packages/cli-engine/src/execution/needs.ts
index b45b5825..7b00318f 100644
--- a/packages/cli-engine/src/execution/needs.ts
+++ b/packages/cli-engine/src/execution/needs.ts
@@ -30,6 +30,9 @@ export type NeedsOutcome =
   | {
       readonly kind: "ok";
       readonly config: unknown;
+      /** The file the config came from, absolute; null when the command
+       *  has no config need and the file was never read. */
+      readonly configFile: string | null;
       /** The credential resolved for a `credentials: "child"` command,
        *  carried forward so the spawn path never re-resolves it. */
       readonly spawnCredential: ActiveCredential | undefined;
@@ -90,6 +93,7 @@ export async function checkNeeds(
   return {
     kind: "ok",
     config: undefined,
+    configFile: null,
     spawnCredential: credentials.spawnCredential,
   };
 }
@@ -270,18 +274,23 @@ async function checkConfiguration(
     loaded,
     invocation,
     configPath ?? CONFIG_FILE_NAME,
+    resolve(invocation.runtime.cwd, loaded.path),
   );
 }
 
 /** Validates the command's needed config section. The validator
  *  owns absence (it receives undefined when the section is missing) and
  *  never throws — a throw is an engine-boundary bug, settled as one.
- *  `configFile` is named in the error so a run under --config points at
- *  the file it actually read. */
+ *  `namedFile` is named in the error so a run under --config points at
+ *  the file it actually read; `configFile` is the same file made
+ *  absolute against cwd, which is what the handler anchors on — the
+ *  loader's own report is resolved because a host loader may hand back
+ *  the path exactly as `--config` gave it. */
 function validateConfigSection(
   section: ConfigSection<unknown>,
   loaded: LoadedConfig,
   invocation: Invocation,
+  namedFile: string,
   configFile: string,
 ): NeedsOutcome {
   const raw = loaded.sections[section.name];
@@ -301,7 +310,7 @@ function validateConfigSection(
     return needsErrored(
       new CliStructuredError(
         "CLI.CONFIG_SECTION_INVALID",
-        `The '${section.name}' section of ${configFile} is invalid.`,
+        `The '${section.name}' section of ${namedFile} is invalid.`,
         {
           nextActions: [
             {
@@ -316,7 +325,12 @@ function validateConfigSection(
     );
   }
   writeSectionWarnings(invocation, validation.diagnostics);
-  return { kind: "ok", config: validation.value, spawnCredential: undefined };
+  return {
+    kind: "ok",
+    config: validation.value,
+    configFile,
+    spawnCredential: undefined,
+  };
 }
 
 /** Diagnostics on an OK validation are warnings: written to stderr as
diff --git a/packages/cli-engine/tests/config.test.ts b/packages/cli-engine/tests/config.test.ts
index 65bfad5b..d8868fe9 100644
--- a/packages/cli-engine/tests/config.test.ts
+++ b/packages/cli-engine/tests/config.test.ts
@@ -1298,3 +1298,105 @@ describe("warnings on a successful section validation", {
     expect(run.stderr).toBe("✔ hi\n");
   });
 });
+
+/**
+ * A relative path inside a config file means "relative to this file",
+ * and a handler can only honour that if it knows which file was read.
+ * The path is absolute whatever the host's loader reported, because a
+ * handler anchoring on its directory must not depend on the loader.
+ */
+describe("ctx.configFile", { timeout: 60_000 }, () => {
+  function probeCommand(section: ConfigSection<ToyConfig>) {
+    return defineCommand({
+      help: { summary: "Reports the config file the run read" },
+      needs: { config: section },
+      handler: async (_args, ctx) =>
+        ok(
+          ctx.present(
+            { data: { configFile: ctx.configFile } },
+            {
+              human: () => [],
+              stdout: () => [],
+              json: () => ({ configFile: ctx.configFile }),
+              next: () => [],
+            },
+          ),
+        ),
+    });
+  }
+
+  function probingCli(loader: Runtime["loadConfig"]) {
+    return createTestCli({
+      commands: { probe: probeCommand(toySection()) },
+      loadConfig: loader,
+    });
+  }
+
+  test("a --config path given relative to cwd arrives absolute", async () => {
+    const cli = probingCli((request) => loadConfig(FIXTURES, request));
+    const run = await cli.run(
+      ["probe", "--config", join("named", "elsewhere.config.ts")],
+      { cwd: FIXTURES },
+    );
+    expect(run.exitCode).toBe(0);
+    expect(run.presented?.data).toEqual({
+      configFile: join(FIXTURES, "named", "elsewhere.config.ts"),
+    });
+  });
+
+  test("without the flag it is the discovered prisma.config.ts in cwd", async () => {
+    const cwd = join(FIXTURES, "discovered");
+    const cli = probingCli((request) => loadConfig(cwd, request));
+    const run = await cli.run(["probe"], { cwd });
+    expect(run.exitCode).toBe(0);
+    expect(run.presented?.data).toEqual({
+      configFile: join(cwd, "prisma.config.ts"),
+    });
+  });
+
+  test("a host loader that reports a relative path is resolved against cwd", async () => {
+    const cli = probingCli(async (configPath) => ({
+      path: configPath ?? "prisma.config.ts",
+      sections: { toy: { greeting: "hi" } },
+      diagnostics: [],
+    }));
+    const run = await cli.run(["probe", "--config", "other.config.ts"], {
+      cwd: "/somewhere/project",
+    });
+    expect(run.exitCode).toBe(0);
+    expect(run.presented?.data).toEqual({
+      configFile: "/somewhere/project/other.config.ts",
+    });
+  });
+
+  test("a command with no config need gets null", async () => {
+    const asked: (string | undefined)[] = [];
+    const cli = createTestCli({
+      commands: {
+        probe: defineCommand({
+          help: { summary: "Reports the config file the run read" },
+          handler: async (_args, ctx) =>
+            ok(
+              ctx.present(
+                { data: { configFile: ctx.configFile }, exitCode: 0 },
+                {
+                  human: () => [],
+                  stdout: () => [],
+                  json: () => ({ configFile: ctx.configFile }),
+                  next: () => [],
+                },
+              ),
+            ),
+        }),
+      },
+      loadConfig: async (configPath) => {
+        asked.push(configPath);
+        return { path: "prisma.config.ts", sections: {}, diagnostics: [] };
+      },
+    });
+    const run = await cli.run(["probe", "--config", "other.config.ts"]);
+    expect(run.exitCode).toBe(0);
+    expect(run.presented?.data).toEqual({ configFile: null });
+    expect(asked).toEqual([]);
+  });
+});
diff --git a/packages/cli-engine/tests/fixtures/config/discovered/prisma.config.ts b/packages/cli-engine/tests/fixtures/config/discovered/prisma.config.ts
new file mode 100644
index 00000000..8d911cff
--- /dev/null
+++ b/packages/cli-engine/tests/fixtures/config/discovered/prisma.config.ts
@@ -0,0 +1,5 @@
+import { definePrismaConfig } from "@prisma/cli-engine";
+
+export default definePrismaConfig({
+  toy: { greeting: "found in cwd" },
+});
diff --git a/packages/cli/package.json b/packages/cli/package.json
index 20c240fe..84976467 100644
--- a/packages/cli/package.json
+++ b/packages/cli/package.json
@@ -49,7 +49,7 @@
   },
   "dependencies": {
     "@manypkg/tools": "^2.1.2",
-    "@prisma/cli-engine": "workspace:0.4.0",
+    "@prisma/cli-engine": "workspace:0.5.0",
     "@prisma/composer-cli": "0.20.0",
     "@prisma/compute-sdk": "0.42.0",
     "@prisma/management-api-sdk": "1.69.0",
diff --git a/packages/prisma/package.json b/packages/prisma/package.json
index 2f69d6a1..1a6804c6 100644
--- a/packages/prisma/package.json
+++ b/packages/prisma/package.json
@@ -50,7 +50,7 @@
   },
   "dependencies": {
     "@manypkg/tools": "^2.1.2",
-    "@prisma/cli-engine": "workspace:0.4.0",
+    "@prisma/cli-engine": "workspace:0.5.0",
     "@prisma/composer-cli": "0.20.0",
     "@prisma/compute-sdk": "0.42.0",
     "@prisma/management-api-sdk": "1.69.0",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 8aadcbc8..82a7295a 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -27,7 +27,7 @@ importers:
         specifier: ^2.1.2
         version: 2.1.2
       '@prisma/cli-engine':
-        specifier: workspace:0.4.0
+        specifier: workspace:0.5.0
         version: link:../cli-engine
       '@prisma/composer-cli':
         specifier: 0.20.0
@@ -207,7 +207,7 @@ importers:
         specifier: ^2.1.2
         version: 2.1.2
       '@prisma/cli-engine':
-        specifier: workspace:0.4.0
+        specifier: workspace:0.5.0
         version: link:../cli-engine
       '@prisma/composer-cli':
         specifier: 0.20.0