Add pdf input for Sonnet (#142)

* llm-claude.el (llm-claude--multipart-content): Handle PDF's in
multipart content.
(llm-capabilities): Add pdf-input.
* llm-integration-test.el (llm-pdf-chat): New integration test.
* llm-models.el (llm-model): Add pdf-input to capabilities docstring.
(llm-models): Add pdf-input to capabilities of Claude 3.5 Sonnet.
* llm.el (llm-media):
(llm-capabilities):  Add pdf-input to documentation.

llm-claude.el

@@ -92,18 +92,22 @@
 
 (defun llm-claude--multipart-content (content)
   "Return CONTENT as a list of Claude multipart content."
-  (vconcat (mapcar (lambda (part)
-                     (cond ((stringp part)
-                            `(:type "text"
-                                    :text ,part))
-                           ((llm-media-p part)
-                            `(:type "image"
-                                    :source (:type "base64"
-                                                   :media_type ,(llm-media-mime-type part)
-                                                   :data ,(base64-encode-string (llm-media-data part) t))))
-                           (t
-                            (error "Unsupported multipart content: %s" part))))
-                   (llm-multipart-parts content))))
+  (vconcat
+   (mapcar (lambda (part)
+             (cond ((stringp part)
+                    `(:type "text"
+                            :text ,part))
+                   ((llm-media-p part)
+                    (let ((source (list :type "base64"
+                                        :media_type (llm-media-mime-type part)
+                                        :data (base64-encode-string (llm-media-data part) t))))
+                      `(:type ,(if (equal (llm-media-mime-type part) "application/pdf")
+                                   "document"
+                                 "image")
+                              :source ,source)))
+                   (t
+                    (error "Unsupported multipart content: %s" part))))
+           (llm-multipart-parts content))))
 
 (cl-defmethod llm-provider-extract-tool-uses ((_ llm-claude) response)
   (let ((content (append (assoc-default 'content response) nil)))
@@ -178,7 +182,7 @@
   "Claude")
 
 (cl-defmethod llm-capabilities ((_ llm-claude))
-  (list 'streaming 'function-calls 'image-input))
+  (list 'streaming 'function-calls 'image-input 'pdf-input))
 
 (cl-defmethod llm-provider-append-to-prompt ((_ llm-claude) prompt result
                                              &optional tool-use-results)

llm-integration-test.el

@@ -290,6 +290,23 @@ else.  We really just want to see if it's in the right ballpark."
       (should (stringp result))
       (should (llm-integration-test-string-eq "owl" (string-trim (downcase result)))))))
 
+(llm-def-integration-test
+  llm-pdf-chat (provider)
+  (when (member 'pdf-input (llm-capabilities provider))
+    (let* ((pdf-data
+            (with-temp-buffer (set-buffer-multibyte nil)
+                              (insert-file-contents-literally
+                               (expand-file-name "test.pdf" llm-integration-current-directory))
+                              (buffer-string)))
+           (result (llm-chat
+                    provider
+                    (llm-make-chat-prompt
+                     (llm-make-multipart
+                      "What symbol occurs in the PDF file?  If you do not see a PDF file, please let me know.  If you do, please answer in one letter, without punctuation or whitespace."
+                      (make-llm-media :mime-type "application/pdf" :data pdf-data))))))
+      (should (stringp result))
+      (should (llm-integration-test-string-eq "x" (string-trim (downcase result)))))))
+
 (llm-def-integration-test llm-json-test (provider)
   (when (member 'json-response (llm-capabilities provider))
     (let ((result (llm-chat

llm-models.el

@@ -30,8 +30,8 @@ NAME is the name of the model, appropriate for showing a user.
 
 CAPABILITIES is a list of symbols representing the capabilities of the
 model, one of `embedding', `generation', `tool-use',
-`image-input', `image-output', `audio-input', `video-input', `caching'
-and `free-software'.
+`image-input', `image-output', `audio-input', `video-input', 'pdf-input',
+`caching' and `free-software'.
 
 REGEX is a regular expression that can be used to identify the model, uniquely (it shouldn't conflict with any other model)"
   name
@@ -103,7 +103,7 @@ REGEX is a regular expression that can be used to identify the model, uniquely (
    ;; https://docs.anthropic.com/en/docs/about-claude/models
    (make-llm-model
     :name "Claude 3.5 Sonnet" :symbol 'claude-3.5-sonnet
-    :capabilities '(generation tool-use image-input caching)
+    :capabilities '(generation tool-use image-input pdf-input caching)
     :context-length 200000
     :regex "claude-3.5-sonnet")
    (make-llm-model

llm.el

@@ -134,8 +134,8 @@ MIME types are accepted by all providers.
 DATA is a (binary) string containing the data.  The string should use
 unibyte encoding.
 
-This should only be used if the `image-input' or `audio-input'
-capability is available, as indicated by `llm-capabilities'."
+This should only be used if the `image-input' or `audio-input' or
+`pdf-input' capability is available, as indicated by `llm-capabilities'."
   mime-type data)
 
 (defun llm--image-to-media (image)
@@ -556,6 +556,8 @@ won't have any partial responses, so basically just operates like
 
 `image-input': the LLM can accept images as input.
 
+`pdf-input': the LLM can accept PDF documents as input.
+
 `json-response': the LLM can be requested to return responses only in
 JSON format.