llama-atmosphere-agent: move model-facing texts into resource files

The system prompt and the run_command description were Java string
concatenations. They are now plain text next to the classes, in
src/main/resources/net/ladenthin/llama/atmosphere/:

- system-prompt.txt          ({workspace}, {shell_section})
- system-prompt-shell.txt    ({shell}; the section with --allow-shell)
- system-prompt-no-shell.txt (the section without it)
- run-command-tool.txt       ({shell}; the tool description)

each with a .license sidecar so REUSE stays green without an SPDX comment
reaching the model. LocalAgent.prompt(name) loads them (UTF-8, trimmed; a
missing file throws). New test promptResourcesLoadAndEveryPlaceholderIsFilled
fails on a missing file or a placeholder left unfilled; the tool-description
test checks the same. README and CLAUDE.md point at the files.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2h8gXyyE5UeimkL9vQv9G

Author: bernardladenthin

CLAUDE.md

@@ -2205,7 +2205,12 @@ a `jvm.config` takes no comments, so REUSE can only read its metadata from that
 `REUSE Compliance Check` job fails on `main` — which is how it was found, the PR run having been cancelled.
 Spotless (palantir) is configured in its own pom; the model-free CI job runs `spotless:check`.
 
-**The default system prompt is general-purpose on purpose — do not narrow it back.** `LocalAgent.systemPrompt`
+**The default system prompt is general-purpose on purpose — do not narrow it back.** Every model-facing
+text is a resource, not a Java literal: `src/main/resources/net/ladenthin/llama/atmosphere/` holds
+`system-prompt.txt`, `system-prompt-shell.txt`, `system-prompt-no-shell.txt` and `run-command-tool.txt`
+(each with a `.license` sidecar for REUSE), loaded by `LocalAgent.prompt(name)` with `{placeholder}`
+substitution; `AgentOptionsTest.promptResourcesLoadAndEveryPlaceholderIsFilled` fails on a missing file or
+an unfilled placeholder. `LocalAgent.systemPrompt`
 and the `ShellTool` description describe `run_command` as running *any* command line through the named
 shell (`ShellTool.shellName()`), not limited to the workspace, and tell the model to run a command rather
 than explain one. The earlier wording ("careful *coding agent*", `run_command` "to build, test or inspect

llama-atmosphere-agent/README.md

@@ -126,6 +126,12 @@ command line on this machine (the shell is named, so the model writes the right
 model should run a command rather than explain one. Without `--allow-shell` it tells the model it
 cannot run commands and to suggest the flag, so the model does not invent a limitation of its own.
 
+The wording is plain text, not Java: [`src/main/resources/net/ladenthin/llama/atmosphere/`](src/main/resources/net/ladenthin/llama/atmosphere/)
+holds `system-prompt.txt` (placeholders `{workspace}` and `{shell_section}`), `system-prompt-shell.txt` /
+`system-prompt-no-shell.txt` (the `{shell_section}` with and without `--allow-shell`; `{shell}` is the
+shell's name) and `run-command-tool.txt` (the `run_command` description the model reads). Edit them
+there to change the default for everyone; `--system` overrides it per run.
+
 This wording matters more than it looks: an earlier default called the agent a *coding agent* and
 described `run_command` as a way to *"build, test or inspect the project"*, and Qwen3-4B then refused
 *"list the docker images"* ("my tools are only for files") although the tool was registered and the

llama-atmosphere-agent/src/main/java/net/ladenthin/llama/atmosphere/LocalAgent.java

@@ -5,8 +5,11 @@
 package net.ladenthin.llama.atmosphere;
 
 import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.PrintStream;
+import java.io.UncheckedIOException;
 import java.nio.charset.StandardCharsets;
 import java.time.Duration;
 import java.util.ArrayList;
@@ -45,6 +48,15 @@ public final class LocalAgent {
     /** Wall-clock bound on one user turn, including every tool round. */
     private static final Duration TURN_TIMEOUT = Duration.ofMinutes(30);
 
+    /** The default system prompt; placeholders {@code {workspace}} and {@code {shell_section}}. */
+    static final String SYSTEM_PROMPT = "system-prompt.txt";
+
+    /** The {@code {shell_section}} with {@code --allow-shell}; placeholder {@code {shell}}. */
+    static final String SHELL_PROMPT = "system-prompt-shell.txt";
+
+    /** The {@code {shell_section}} without {@code --allow-shell}. */
+    static final String NO_SHELL_PROMPT = "system-prompt-no-shell.txt";
+
     private static final Duration SHELL_TIMEOUT = Duration.ofSeconds(120);
     private static final int SHELL_MAX_OUTPUT_CHARS = 20_000;
 
@@ -217,7 +229,8 @@ static ModelParameters modelParameters(AgentOptions options) {
      * requests such as "list the docker images" even though {@code run_command} could do it. With
      * {@code --allow-shell} the prompt therefore states that any command line is allowed and that the
      * model should run a command rather than explain one; without it, the prompt says so honestly
-     * instead of letting the model invent a limitation.
+     * instead of letting the model invent a limitation. The text itself is in the resources
+     * {@value #SYSTEM_PROMPT}, {@value #SHELL_PROMPT} and {@value #NO_SHELL_PROMPT} (see {@link #prompt}).
      *
      * @param options the options
      * @return the system prompt
@@ -226,19 +239,32 @@ static String systemPrompt(AgentOptions options) {
         if (options.getSystemPrompt() != null) {
             return options.getSystemPrompt();
         }
-        String files = " The file tools ls, read_file, write_file, edit_file, glob, grep, delete and rename work"
-                + " on the directory " + options.getWorkspace() + "; their paths are relative to it.";
-        String shell = options.isAllowShell()
-                ? " You have full shell access: run_command executes any command line through "
-                        + ShellTool.shellName() + " on this machine, starting in that directory but not"
-                        + " limited to it, e.g. docker, git, package managers, build tools or system"
-                        + " information. When the user asks about this machine or wants something done,"
-                        + " run the command instead of explaining how to do it."
-                : " You cannot run shell commands in this session; if a request needs one, say so and"
-                        + " suggest restarting the agent with --allow-shell.";
-        return "You are a helpful general-purpose assistant running locally on the user's computer, with"
-                + " tools to act on it." + files + shell
-                + " Work step by step: read a file before you edit it, check the result after a change,"
-                + " and finish with a short summary. Answer in the user's language.";
+        String shellSection = options.isAllowShell()
+                ? prompt(SHELL_PROMPT).replace("{shell}", ShellTool.shellName())
+                : prompt(NO_SHELL_PROMPT);
+        return prompt(SYSTEM_PROMPT)
+                .replace("{workspace}", options.getWorkspace().toString())
+                .replace("{shell_section}", shellSection);
+    }
+
+    /**
+     * A prompt text from the resources next to this class, trimmed.
+     *
+     * <p>The wording lives in {@code src/main/resources/net/ladenthin/llama/atmosphere/*.txt} so it can
+     * be read and edited as text; {@code {placeholders}} are filled in by {@link #systemPrompt}.
+     *
+     * @param name the file name, e.g. {@value #SYSTEM_PROMPT}
+     * @return the file content without leading or trailing whitespace
+     * @throws IllegalStateException when the resource is missing from the jar
+     */
+    static String prompt(String name) {
+        try (InputStream in = LocalAgent.class.getResourceAsStream(name)) {
+            if (in == null) {
+                throw new IllegalStateException("Prompt resource missing: " + name);
+            }
+            return new String(in.readAllBytes(), StandardCharsets.UTF_8).strip();
+        } catch (IOException e) {
+            throw new UncheckedIOException("Cannot read prompt resource " + name, e);
+        }
     }
 }

llama-atmosphere-agent/src/main/java/net/ladenthin/llama/atmosphere/ShellTool.java

@@ -24,6 +24,9 @@ public final class ShellTool {
     /** Tool name as offered to the model. */
     public static final String TOOL_NAME = "run_command";
 
+    /** The tool description the model reads (a resource next to this class); placeholder {@code {shell}}. */
+    static final String DESCRIPTION_RESOURCE = "run-command-tool.txt";
+
     private static final String PARAM_COMMAND = "command";
     private static final String PARAM_TIMEOUT = "timeout_seconds";
 
@@ -39,11 +42,7 @@ private ShellTool() {}
      */
     public static ToolDefinition definition(Path workspace, Duration defaultTimeout, int maxOutputChars) {
         return ToolDefinition.builder(
-                        TOOL_NAME,
-                        "Run any command line on this machine through " + shellName() + " and return its exit"
-                                + " code and output (stdout and stderr merged). It starts in the workspace"
-                                + " directory but is not limited to it: use it for every task a terminal can do,"
-                                + " e.g. docker, git, package managers, build tools or system information.")
+                        TOOL_NAME, LocalAgent.prompt(DESCRIPTION_RESOURCE).replace("{shell}", shellName()))
                 .parameter(PARAM_COMMAND, "The command line to run through " + shellName(), "string", true)
                 .parameter(PARAM_TIMEOUT, "Seconds to wait before the command is killed", "integer", false)
                 .executor(args -> {

llama-atmosphere-agent/src/main/resources/net/ladenthin/llama/atmosphere/run-command-tool.txt

@@ -0,0 +1 @@
+Run any command line on this machine through {shell} and return its exit code and output (stdout and stderr merged). It starts in the workspace directory but is not limited to it: use it for every task a terminal can do, e.g. docker, git, package managers, build tools or system information.

llama-atmosphere-agent/src/main/resources/net/ladenthin/llama/atmosphere/run-command-tool.txt.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2026 Bernard Ladenthin <bernard.ladenthin@gmail.com>
+
+SPDX-License-Identifier: MIT

llama-atmosphere-agent/src/main/resources/net/ladenthin/llama/atmosphere/system-prompt-no-shell.txt

@@ -0,0 +1 @@
+You cannot run shell commands in this session; if a request needs one, say so and suggest restarting the agent with --allow-shell.

llama-atmosphere-agent/src/main/resources/net/ladenthin/llama/atmosphere/system-prompt-no-shell.txt.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2026 Bernard Ladenthin <bernard.ladenthin@gmail.com>
+
+SPDX-License-Identifier: MIT

llama-atmosphere-agent/src/main/resources/net/ladenthin/llama/atmosphere/system-prompt-shell.txt

@@ -0,0 +1 @@
+You have full shell access: run_command executes any command line through {shell} on this machine, starting in that directory but not limited to it, e.g. docker, git, package managers, build tools or system information. When the user asks about this machine or wants something done, run the command instead of explaining how to do it.

llama-atmosphere-agent/src/main/resources/net/ladenthin/llama/atmosphere/system-prompt-shell.txt.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2026 Bernard Ladenthin <bernard.ladenthin@gmail.com>
+
+SPDX-License-Identifier: MIT