Add support for Anthropic API

README.md

@@ -5,7 +5,8 @@ The __ai-cli__
 library detects programs that offer interactive command-line editing
 through the __readline__ library,
 and modifies their interface to allow obtaining help from a GPT
-large language model, such as OpenAI's or one provided through a
+large language model server, such as Anthropic's or OpenAI's,
+or one provided through a
 [llama.cpp](https://github.com/ggerganov/llama.cpp) server.
 Think of it as a command line copilot.
 
@@ -85,15 +86,20 @@ make install PREFIX=~
   the Homebrew library directory, e.g.
   `export DYLD_LIBRARY_PATH=/opt/homebrew/lib:$DYLD_LIBRARY_PATH`.
 * Perform one of the following.
-  * [Obtain your OpenAI API key](https://platform.openai.com/api-keys),
+  * Obtain your
+    [Anthropic API key](https://console.anthropic.com/settings/keys)
+    or
+    [OpenAI API key](https://platform.openai.com/api-keys)
     and configure it in the `.aicliconfig` file in your home directory.
-    This is done with a `key={key}` entry in the file's `[openai]` section.
-    In addition, add `api=openai` in the file's `[general]` section.
+    This is done with a `key={key}` entry in the file's
+    `[anthropic]` or `[openai]` section.
+    In addition, add `api=anthropic` or `api=openai` in the file's
+    `[general]` section.
     See the file [ai-cli-config](src/ai-cli-config) to understand how configuration
     files are structured.
+    Anthropic currently provides free trial credits to new users.
     Note that OpenAI API access requires a different (usage-based)
     subscription from the ChatGPT one.
-    OpenAI currently provides free trial credits to new users.
   * Configure a [llama.cpp](https://github.com/ggerganov/llama.cpp) server
     and list its `endpoint` (e.g. `endpoint=http://localhost:8080/completion`
     in the configuration file's `[llamacpp]` section.

src/Makefile

@@ -6,7 +6,8 @@ MANPREFIX ?= "$(PREFIX)/share/man/"
 SHAREPREFIX ?= "$(PREFIX)/share/ai-cli"
 
 PROGS=rl_driver $(SHARED_LIB)
-RL_SRC=ai_cli.c config.c ini.c openai_fetch.c llamacpp_fetch.c support.c
+RL_SRC=ai_cli.c config.c ini.c anthropic_fetch.c openai_fetch.c \
+       llamacpp_fetch.c support.c
 TEST_SRC=$(wildcard *_test.c)
 LIB=-lcurl -ljansson
 

src/ai-cli-config

@@ -13,6 +13,15 @@ temperature = 0.7
 ; User-specific: add it in a local protected file
 ; key =
 
+[anthropic]
+endpoint = https://api.anthropic.com/v1/messages
+version = 2023-06-01
+; Most capable. Cost (3/2024): Input: $15 / MTok, Output: $75 / MTok
+model = claude-3-opus-20240229
+; User-specific: add it in a local protected file
+; key =
+max_tokens = 256
+
 [llamacpp]
 endpoint = http://localhost:8080/completion
 

src/ai_cli.5

@@ -101,9 +101,46 @@ followed by a space, before being added to the edit buffer.
 \fItimestamp=\fR
 .RS 4
 Setting \fItimestamp\fP to \fItrue\fP will cause the log file
-to include the timesamp (in ISO format) of each request or response.
+to include the timestamp (in ISO format) of each request or response.
 .RE
 
+.SH [ANTHROPIC] SECTION OPTIONS
+These options tailor the behavior of queries made to the Anthropic servers.
+Refer to the
+.UR "https://docs.anthropic.com/claude/reference/messages_post"
+Anthropic API documentation
+.UE
+for more details.
+
+.PP
+\fImodel=\fR
+.RS 4
+The Anthropic model to use, e.g.
+.IR claude-3-opus-20240229 .
+This affects performance and pricing.
+.RE
+.PP
+\fIendpoint=\fR
+.RS 4
+The URL of the API endpoint, e.g.  \fChttps://api.anthropic.com/v1/messages\fP.
+.RE
+.PP
+\fImax_tokens=\fR
+.PP
+\fItemperature=\fR
+.PP
+\fItop_k=\fR
+.PP
+\fItop_p=\fR
+.PP
+\fIversion=\fR
+.RS 4
+The version to supply to the
+.I anthropic-version
+HTTP header field.
+.RE
+.PP
+
 .SH [LLAMACPP] SECTION OPTIONS
 These options tailor the behavior of the llama.cpp
 queries.
@@ -264,7 +301,7 @@ The names and order of configuration files are documented in
 Diomidis Spinellis ([email protected])
 
 .SH COPYRIGHT
-Copyright 2023 Diomidis Spinellis
+Copyright 2023-2024 Diomidis Spinellis
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.

src/ai_cli.7

@@ -12,7 +12,7 @@ Set the
 .B DYLD_INSERT_LIBRARIES
 (under macOS)
 environment variable to load the library using its full path.
-Obtain your OpenAI API key and configure it in the
+Obtain your Anthropic or OpenAI API key and configure it in the
 .B .aicliconfig
 file.
 Alternatively, setup a running
@@ -115,7 +115,7 @@ configuration files.
 Diomidis Spinellis ([email protected])
 
 .SH COPYRIGHT
-Copyright 2023 Diomidis Spinellis
+Copyright 2023-2024 Diomidis Spinellis
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.

src/ai_cli.c

@@ -28,6 +28,8 @@
 #include <readline/history.h>
 
 #include "config.h"
+
+#include "anthropic_fetch.h"
 #include "llamacpp_fetch.h"
 #include "openai_fetch.h"
 
@@ -133,6 +135,11 @@ setup(void)
 		fetch = openai_fetch;
 		REQUIRE(openai, key);
 		REQUIRE(openai, endpoint);
+	} else if (strcmp(config.general_api, "anthropic") == 0) {
+		fetch = anthropic_fetch;
+		REQUIRE(anthropic, key);
+		REQUIRE(anthropic, endpoint);
+		REQUIRE(anthropic, version);
 	} else if (strcmp(config.general_api, "llamacpp") == 0) {
 		fetch = llamacpp_fetch;
 		REQUIRE(llamacpp, endpoint);

src/all_tests.c

@@ -1,8 +1,29 @@
+/*-
+ *
+ *  ai-cli - readline wrapper to obtain a generative AI suggestion
+ *  Unit test driver
+ *
+ *  Copyright 2023-2024 Diomidis Spinellis
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
 #include <stdio.h>
 
 #include "CuTest.h"
 
 CuSuite* cu_config_suite();
+CuSuite* cu_fetch_anthropic_suite();
 CuSuite* cu_fetch_openai_suite();
 CuSuite* cu_fetch_llamacpp_suite();
 CuSuite* cu_support_suite();
@@ -14,6 +35,7 @@ run_all_tests(void)
 	CuSuite* suite = CuSuiteNew();
 
 	CuSuiteAddSuite(suite, cu_config_suite());
+	CuSuiteAddSuite(suite, cu_fetch_anthropic_suite());
 	CuSuiteAddSuite(suite, cu_fetch_openai_suite());
 	CuSuiteAddSuite(suite, cu_fetch_llamacpp_suite());
 	CuSuiteAddSuite(suite, cu_support_suite());

src/anthropic_fetch.c

@@ -0,0 +1,188 @@
+/*-
+ *
+ *  ai-cli - readline wrapper to obtain a generative AI suggestion
+ *  anthropic access function
+ *
+ *  Copyright 2023-2024 Diomidis Spinellis
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <curl/curl.h>
+#include <readline/history.h>
+#include <jansson.h>
+
+#include "config.h"
+#include "support.h"
+#include "anthropic_fetch.h"
+
+// HTTP headers
+static char *key_header;
+static char *version_header;
+
+// Return the response content from an Anthropic JSON response
+STATIC char *
+anthropic_get_response_content(const char *json_response)
+{
+	json_error_t error;
+	json_t *root = json_loads(json_response, 0, &error);
+	if (!root) {
+		readline_printf("\nanthropic JSON error: on line %d: %s\n", error.line, error.text);
+		return NULL;
+	}
+
+	char *ret;
+	json_t *content = json_object_get(root, "content");
+	if (content) {
+		json_t *first_content = json_array_get(content, 0);
+		json_t *text = json_object_get(first_content, "text");
+		ret = safe_strdup(json_string_value(text));
+	} else {
+		json_t *error = json_object_get(root, "error");
+		if (error) {
+			json_t *message = json_object_get(error, "message");
+			readline_printf("\nAnthropic invocation error: %s\n", json_string_value(message));
+		} else
+			readline_printf("\nAnthropic invocation error: %s\n", json_response);
+		ret = NULL;
+	}
+
+	json_decref(root);
+	return ret;
+}
+
+/*
+ * Initialize anthropic connection
+ * Return 0 on success -1 on error
+ */
+static int
+initialize(config_t *config)
+{
+	if (config->general_verbose)
+		fprintf(stderr, "\nInitializing Anthropic, program name [%s] system prompt to use [%s]\n",
+		    short_program_name(), config->prompt_system);
+	safe_asprintf(&key_header, "x-api-key: %s", config->anthropic_key);
+	safe_asprintf(&version_header, "anthropic-version: %s", config->anthropic_version);
+	return curl_initialize(config);
+}
+
+/*
+ * Fetch response from the anthropic API given the provided prompt.
+ * Provide context in the form of n-shot prompts and history prompts.
+ */
+char *
+anthropic_fetch(config_t *config, const char *prompt, int history_length)
+{
+	CURLcode res;
+
+	if (!curl && initialize(config) < 0)
+		return NULL;
+
+	if (config->general_verbose)
+		fprintf(stderr, "\nContacting Llamacpp API...\n");
+
+	struct curl_slist *headers = NULL;
+	headers = curl_slist_append(headers, "content-type: application/json");
+	headers = curl_slist_append(headers, key_header);
+	headers = curl_slist_append(headers, version_header);
+
+	struct string json_response;
+	string_init(&json_response, "");
+
+	struct string json_request;
+	string_init(&json_request, "{\n");
+
+	string_appendf(&json_request, "  \"model\": %s,\n",
+	    json_escape(config->anthropic_model));
+	string_appendf(&json_request, "  \"max_tokens\": %d,\n",
+	    config->anthropic_max_tokens);
+
+	char *system_role = system_role_get(config);
+	string_appendf(&json_request, "  \"system\": %s,\n",
+	    json_escape(system_role));
+	free(system_role);
+
+	// Add configuration settings
+	if (config->anthropic_temperature_set)
+		string_appendf(&json_request, "  \"temperature\": %g,\n", config->anthropic_temperature);
+	if (config->anthropic_top_k_set)
+		string_appendf(&json_request, "  \"top_k\": %d,\n", config->anthropic_top_k);
+	if (config->anthropic_top_p_set)
+		string_appendf(&json_request, "  \"top_p\": %g,\n", config->anthropic_top_p);
+
+	string_append(&json_request, "  \"messages\": [\n");
+
+	// Add user and assistant n-shot prompts
+	for (int i = 0; i < NPROMPTS; i++) {
+		if (config->prompt_user[i])
+			string_appendf(&json_request,
+			    "    {\"role\": \"user\", \"content\": %s},\n",
+			    json_escape(config->prompt_user[i]));
+		if (config->prompt_assistant[i])
+			string_appendf(&json_request,
+			    "    {\"role\": \"assistant\", \"content\": %s},\n",
+			    json_escape(config->prompt_assistant[i]));
+	}
+
+	// Add history prompts as context
+	bool context_explained = false;
+	for (int i = config->prompt_context - 1; i >= 0; --i) {
+		HIST_ENTRY *h = history_get(history_length - 1 - i);
+		if (h == NULL)
+			continue;
+		if (!context_explained) {
+			context_explained = true;
+			string_appendf(&json_request,
+			    "    {\"role\": \"user\", \"content\": \"Before my final prompt to which I expect a reply, I am also supplying you as context with one or more previously issued commands, to which you simply reply OK\"},\n");
+			string_appendf(&json_request,
+			    "    {\"role\": \"assistant\", \"content\": \"OK\"},\n");
+		}
+		string_appendf(&json_request,
+		    "    {\"role\": \"user\", \"content\": %s},\n",
+		    json_escape(h->line));
+		string_appendf(&json_request,
+		    "    {\"role\": \"assistant\", \"content\": \"OK\"},\n");
+	}
+
+	// Finally, add the user prompt
+	string_appendf(&json_request,
+	    "    {\"role\": \"user\", \"content\": %s}\n", json_escape(prompt));
+	string_append(&json_request, "  ]\n}\n");
+
+	write_log(config, json_request.ptr);
+
+	curl_easy_setopt(curl, CURLOPT_URL, config->anthropic_endpoint);
+	curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
+	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, string_write);
+	curl_easy_setopt(curl, CURLOPT_WRITEDATA, &json_response);
+	curl_easy_setopt(curl, CURLOPT_POSTFIELDS, json_request.ptr);
+
+	res = curl_easy_perform(curl);
+
+	if (res != CURLE_OK) {
+		free(json_request.ptr);
+		readline_printf("\nAnthropic API call failed: %s\n",
+		    curl_easy_strerror(res));
+		return NULL;
+	}
+
+	write_log(config, json_response.ptr);
+
+	char *text_response = anthropic_get_response_content(json_response.ptr);
+	free(json_request.ptr);
+	free(json_response.ptr);
+	return text_response;
+}