Compact generated system prompt blocks by flattening XML wrappers and removing duplicated guidance

actions/setup/md/cache_memory_prompt.md

@@ -1,5 +1,5 @@
 <cache-memory>
-<path>__GH_AW_CACHE_DIR__</path>__GH_AW_CACHE_DESCRIPTION__
-<properties>Persistent read/write storage across workflow runs via Actions cache. Last write wins.</properties>__GH_AW_ALLOWED_EXTENSIONS__
-<cache-miss-guidance>If you look for data in the cache and do not find any, call the `missing_data` tool with `data_type: "cache_memory"` and `reason: "cache_memory_miss"` to signal that the cache does not contain the expected information.</cache-miss-guidance>
+Path: `__GH_AW_CACHE_DIR__`__GH_AW_CACHE_DESCRIPTION__
+Persistent read/write storage across workflow runs via Actions cache. Last write wins.__GH_AW_ALLOWED_EXTENSIONS__
+If you look for data in the cache and do not find any, call the `missing_data` tool with `data_type: "cache_memory"` and `reason: "cache_memory_miss"` to signal that the cache does not contain the expected information.
 </cache-memory>

actions/setup/md/cache_memory_prompt_multi.md

@@ -1,8 +1,7 @@
 <cache-memory>
 __GH_AW_CACHE_LIST__
-<properties>Persistent read/write storage across workflow runs via Actions cache. Last write wins.</properties>__GH_AW_ALLOWED_EXTENSIONS__
-<examples>
+Persistent read/write storage across workflow runs via Actions cache. Last write wins.__GH_AW_ALLOWED_EXTENSIONS__
+Examples:
 __GH_AW_CACHE_EXAMPLES__
-</examples>
-<cache-miss-guidance>If you look for data in the cache and do not find any, call the `missing_data` tool with `data_type: "cache_memory"` and `reason: "cache_memory_miss"` to signal that the cache does not contain the expected information.</cache-miss-guidance>
+If you look for data in the cache and do not find any, call the `missing_data` tool with `data_type: "cache_memory"` and `reason: "cache_memory_miss"` to signal that the cache does not contain the expected information.
 </cache-memory>

actions/setup/md/markdown.md

@@ -1,3 +1,3 @@
 <markdown-generation>
-<rule>Only use 4-backtick fences when the block literally contains triple-backtick fences inside it; otherwise use standard 3-backtick fences. Use GitHub Flavored Markdown.</rule>
+Only use 4-backtick fences when the block literally contains triple-backtick fences inside it; otherwise use standard 3-backtick fences. Use GitHub Flavored Markdown.
 </markdown-generation>

actions/setup/md/safe_outputs_prompt.md

@@ -1,5 +1,4 @@
 <safe-outputs>
-<instructions>
 gh CLI is NOT authenticated. Use safeoutputs MCP server tools for GitHub writes and completion signaling — tool calls required.
 
 **CRITICAL: You MUST call one of the safe-output tools before finishing.** You must call at least one tool from the `<safe-output-tools>` list; using non-safe-output tools does not satisfy this requirement. Multiple calls are allowed up to each tool's configured limit. If no GitHub action was taken (no issues, comments, PRs, etc. were created or updated), you MUST call `noop` with a message explaining why no action was needed. This requirement still applies even if the workflow/task prompt forgets to ask for `noop` or does not mention safe outputs at all. Failing to call any safe-output tool is the #1 cause of workflow failures. Do NOT end your response without calling at least one safe-output tool.
@@ -10,10 +9,7 @@ Safe-output calls are write-once declarations for real downstream side effects.
 
 **Do not inspect infrastructure internals.** When a tool or command fails, do not inspect Docker sockets (`/var/run/docker.sock`), mount tables (`/proc/self/mounts`), container networking (`/proc/net`), `/host` paths, git object storage internals, or container-runtime environment internals. These are outside your control; use `report_incomplete` after the retry limit.
 
-When no action is needed, call `noop` with a short status message explaining what you checked and why no action was required. Never skip `noop` due to missing prompt instructions.
-
 temporary_id: optional cross-reference field. Canonical form: '#aw_' followed by 3–12 alphanumeric or underscore characters — e.g., '#aw_abc1', '#aw_pr_fix'. Pattern: /^#?aw_[A-Za-z0-9_]{3,12}$/i (the '#' prefix is optional; bare 'aw_abc1' is accepted and normalised to '#aw_abc1' automatically). Use this form for all field values (temporary_id, item_number, issue_number, parent, etc.). In body/markdown text, '#aw_abc1' references are replaced with the real issue/PR number after creation. Omit entirely when not needed.
 
-**Note**: safeoutputs tools do NOT support `@filename` file name expansion. Always provide content inline — do not use `@<filename>` references in tool arguments.
-</instructions>
+**Note**: safeoutputs tools do NOT support `@filename` file name expansion. Always provide content inline — do not use `@filename` references in tool arguments.
 </safe-outputs>

actions/setup/md/temp_folder_prompt.md

@@ -2,12 +2,6 @@
 <path>/tmp/gh-aw/agent/</path>
 <instruction>When you need to create temporary files or directories during your work, always use the /tmp/gh-aw/agent/ directory that has been pre-created for you. Do NOT use the root /tmp/ directory directly.</instruction>
 </temporary-files>
-<file-editing>
-<allowed-paths>
-Do NOT attempt to edit files outside these directories as you do not have the necessary permissions.
-</file-editing>
 <environment-limitations>
-<docker>
 Docker in Docker is not supported.
-</docker>
 </environment-limitations>

pkg/workflow/cache.go

@@ -798,11 +798,11 @@ func buildCacheMemoryPromptSection(config *CacheMemoryConfig) *PromptSection {
 		}
 
 		// Build allowed extensions text.
-		// When non-empty, wrap as an XML element so the agent knows about file-type restrictions.
+		// When non-empty, add a compact plain-text restriction line.
 		// When empty (all extensions allowed), the placeholder is replaced with nothing.
 		var allowedExtsText string
 		if len(cache.AllowedExtensions) > 0 {
-			allowedExtsText = "\n<allowed-extensions>" + strings.Join(cache.AllowedExtensions, ", ") + "</allowed-extensions>"
+			allowedExtsText = "\nAllowed file extensions: " + strings.Join(cache.AllowedExtensions, ", ") + "."
 		}
 
 		cacheLog.Printf("Building cache memory prompt section with env vars: cache_dir=%s, description=%s, allowed_extensions=%v", cacheDir, descriptionText, cache.AllowedExtensions)
@@ -836,7 +836,7 @@ func buildCacheMemoryPromptSection(config *CacheMemoryConfig) *PromptSection {
 
 	// Build allowed extensions text.
 	// Compute the union of all allowed extensions across all caches.
-	// When non-empty, wrap as an XML element so the agent knows about file-type restrictions.
+	// When non-empty, add a compact plain-text restriction line.
 	// When empty (all extensions allowed for all caches), the placeholder is replaced with nothing.
 	allSame := true
 	for i := 1; i < len(config.Caches); i++ {
@@ -873,7 +873,7 @@ func buildCacheMemoryPromptSection(config *CacheMemoryConfig) *PromptSection {
 
 	var allowedExtsText string
 	if len(extsUnion) > 0 {
-		allowedExtsText = "\n<allowed-extensions>" + strings.Join(extsUnion, ", ") + "</allowed-extensions>"
+		allowedExtsText = "\nAllowed file extensions: " + strings.Join(extsUnion, ", ") + "."
 	}
 
 	// Build cache examples

pkg/workflow/cache_memory_prompt_test.go

@@ -49,9 +49,8 @@ func TestBuildCacheMemoryPromptSection_SingleDefaultCacheWithAllowedExtensions(t
 
 	require.NotNil(t, section, "Should return a prompt section")
 	require.NotNil(t, section.EnvVars, "Should have environment variables")
-	// Allowed extensions should be wrapped in an XML element for the agent prompt
-	assert.Equal(t, "\n<allowed-extensions>.json, .txt</allowed-extensions>", section.EnvVars["GH_AW_ALLOWED_EXTENSIONS"],
-		"Should wrap allowed extensions in XML element")
+	assert.Equal(t, "\nAllowed file extensions: .json, .txt.", section.EnvVars["GH_AW_ALLOWED_EXTENSIONS"],
+		"Should include allowed extensions guidance")
 }
 
 func TestBuildCacheMemoryPromptSection_SingleDefaultCacheWithDescription(t *testing.T) {
@@ -131,8 +130,8 @@ func TestBuildCacheMemoryPromptSection_MultipleCachesWithAllowedExtensions(t *te
 	require.NotNil(t, section, "Should return a prompt section")
 	require.NotNil(t, section.EnvVars, "Should have environment variables")
 	// Union of .json, .jsonl, .txt — sorted
-	assert.Equal(t, "\n<allowed-extensions>.json, .jsonl, .txt</allowed-extensions>", section.EnvVars["GH_AW_ALLOWED_EXTENSIONS"],
-		"Should wrap union of allowed extensions in XML element")
+	assert.Equal(t, "\nAllowed file extensions: .json, .jsonl, .txt.", section.EnvVars["GH_AW_ALLOWED_EXTENSIONS"],
+		"Should include union of allowed extensions guidance")
 }
 
 func TestBuildCacheMemoryPromptSection_SingleNonDefaultCache(t *testing.T) {