diff --git a/Makefile b/Makefile
index b1a26b86..974d0191 100644
--- a/Makefile
+++ b/Makefile
@@ -28,7 +28,7 @@ ${PREFIX}/bin/dist: version/version.go $(shell find . -type f -name '*.go')
 	@echo "+ $@"
 	@go build -o $@ ${GO_LDFLAGS} ./cmd/dist
 
-doc/spec/api.md: doc/spec/api.md.tmpl ${PREFIX}/bin/registry-api-descriptor-template
+docs/spec/api.md: docs/spec/api.md.tmpl ${PREFIX}/bin/registry-api-descriptor-template
 	./bin/registry-api-descriptor-template $< > $@
 
 vet:
diff --git a/docs/spec/api.md b/docs/spec/api.md
index 4512c22f..032ddcf3 100644
--- a/docs/spec/api.md
+++ b/docs/spec/api.md
@@ -2375,7 +2375,7 @@ The following parameters should be specified on the request:
 204 No Content
 Location: <blob location>
 Content-Range: <start of range>-<end of range, inclusive>
-Content-Length: <length of chunk>
+Content-Length: 0
 Docker-Content-Digest: <digest>
 ```
 
@@ -2385,9 +2385,9 @@ The following headers will be returned with the response:
 
 |Name|Description|
 |----|-----------|
-|`Location`||
+|`Location`|The canonical location of the blob for retrieval|
 |`Content-Range`|Range of bytes identifying the desired block of content represented by the body. Start must match the end of offset retrieved via status check. Note that this is a non-standard use of the `Content-Range` header.|
-|`Content-Length`|Length of the chunk being uploaded, corresponding the length of the request body.|
+|`Content-Length`|The `Content-Length` header must be zero and the body must be empty.|
 |`Docker-Content-Digest`|Digest of the targeted content for the request.|
 
 
diff --git a/registry/api/v2/descriptors.go b/registry/api/v2/descriptors.go
index 73f8b463..833bff8b 100644
--- a/registry/api/v2/descriptors.go
+++ b/registry/api/v2/descriptors.go
@@ -1190,9 +1190,10 @@ var routeDescriptors = []RouteDescriptor{
 								StatusCode:  http.StatusNoContent,
 								Headers: []ParameterDescriptor{
 									{
-										Name:   "Location",
-										Type:   "url",
-										Format: "<blob location>",
+										Name:        "Location",
+										Type:        "url",
+										Format:      "<blob location>",
+										Description: "The canonical location of the blob for retrieval",
 									},
 									{
 										Name:        "Content-Range",
@@ -1200,12 +1201,7 @@ var routeDescriptors = []RouteDescriptor{
 										Format:      "<start of range>-<end of range, inclusive>",
 										Description: "Range of bytes identifying the desired block of content represented by the body. Start must match the end of offset retrieved via status check. Note that this is a non-standard use of the `Content-Range` header.",
 									},
-									{
-										Name:        "Content-Length",
-										Type:        "integer",
-										Format:      "<length of chunk>",
-										Description: "Length of the chunk being uploaded, corresponding the length of the request body.",
-									},
+									contentLengthZeroHeader,
 									digestHeader,
 								},
 							},