bind artifact completion to required output path

src/clean_agent_preview.py

@@ -1455,6 +1455,36 @@ def execution_targets_required_artifact(tool_name, arguments, required_artifacts
     return any(str(path or '').rstrip('/') in serialized for path in required_artifacts)
 
 
+def artifact_completion_tool_schemas(offered_schemas, required_artifacts):
+    """Bind the sole artifact writer to the runner-declared output file.
+
+    This applies only after native execution enters its reserved artifact-write
+    phase.  A JSON-Schema ``const`` gives the provider the exact destination
+    instead of relying on it to recover the path from a long conversation.
+    Multiple outputs and directory targets stay unconstrained because choosing
+    one of those paths requires model intent.
+    """
+    targets = [str(path or '').strip().rstrip('/') for path in required_artifacts]
+    targets = [path for path in targets if path and Path(path).suffix]
+    if len(targets) != 1 or len(tuple(required_artifacts or ())) != 1:
+        return offered_schemas
+    target = targets[0]
+    bound = copy.deepcopy(offered_schemas)
+    for schema in bound:
+        function = schema.get('function') or {}
+        if canonical(function.get('name')) != 'write_file':
+            continue
+        properties = (function.get('parameters') or {}).get('properties') or {}
+        path_schema = properties.get('path')
+        if not isinstance(path_schema, dict):
+            continue
+        path_schema['const'] = target
+        path_schema['description'] = (
+            f'Write this exact required artifact path: {target}'
+        )
+    return bound
+
+
 def protocol_safe_tool_calls(calls):
     """Keep malformed model calls out of the next provider request."""
     safe_calls = copy.deepcopy(calls)
@@ -4334,6 +4364,10 @@ async def stream_preview(*, endpoint_url, model, messages, headers, turn_contrac
                             canonical(schema['function']['name']), 0
                         ) < round_number
                     ]
+                if artifact_write_phase and not successful_artifact_write:
+                    round_offered = artifact_completion_tool_schemas(
+                        round_offered, required_artifacts,
+                    )
                 research_choice = None
                 if not required_artifacts:
                     round_offered, research_choice, _ = bounded_research_tool_policy(

tests/test_clean_agent_preview.py

@@ -5,7 +5,7 @@ import jsonschema
 import pytest
 import re
 
-from src.clean_agent_preview import conversation, readonly_call, preview_call_allowed, evaluate_preview_call, authorized_write_families, compact_schemas, normalize_preview_function_args, normalize_preview_call_args, private_browser_dom_batch, private_browser_state_transition, private_browser_success_repeat_limit, stream_preview, denied_response, execution_has_write_effect, requests_mutation, claims_completion, recent_successful_write_families, scope_preview_contract, multimodal_image_count, attachment_reference_count, active_document_context_message, active_email_context_message, targets_active_editor, active_editor_whole_draft_request, active_editor_suggestion_request, scope_active_editor_contract, native_execution_limits, interactive_execution_limit, runtime_required_artifacts, execution_targets_required_artifact, document_suggestions_event, document_suggestion_quality_error, required_read_tool_choice, required_active_editor_tool_choice, sealed_read_arguments, email_identifier_error, requested_item_limit, contract_item_limit, notes_terminal_response, documents_terminal_response, shell_listing_terminal_response, shell_output_terminal_response, direct_shell_output_request, ui_panel_terminal_response, ui_toggle_state_result, calendar_terminal_response, memory_terminal_response, tasks_terminal_response, task_list_requires_synthesis, skills_terminal_response, cookbook_servers_terminal_response, prior_short_answer_for_no_tool_summary, prior_collection_repeat_answer, prior_failed_operation_answer, prior_cookbook_server_answer, prior_workspace_path_answer, prior_web_source_answer, bounded_web_evidence_answer, inherit_referential_read_arguments, normalized_search_intent, requested_web_source_links, web_source_links, requested_web_link_limit, preserve_requested_web_recency, ground_referenced_note_content, note_search_result_empty, note_referent_error, research_referent_error, private_browser_open_url, private_browser_effective_url, web_fetch_observation_is_boilerplate, broad_current_web_request, record_tool_execution, align_structured_tool_history, provider_request_messages, provider_compatible_tool_choice_request, offered_tool_alias, dependent_write_prerequisite_error, bounded_research_tool_policy, retrieved_source_urls, serialize_required_email_attachment_chain
+from src.clean_agent_preview import conversation, readonly_call, preview_call_allowed, evaluate_preview_call, authorized_write_families, compact_schemas, normalize_preview_function_args, normalize_preview_call_args, private_browser_dom_batch, private_browser_state_transition, private_browser_success_repeat_limit, stream_preview, denied_response, execution_has_write_effect, requests_mutation, claims_completion, recent_successful_write_families, scope_preview_contract, multimodal_image_count, attachment_reference_count, active_document_context_message, active_email_context_message, targets_active_editor, active_editor_whole_draft_request, active_editor_suggestion_request, scope_active_editor_contract, native_execution_limits, interactive_execution_limit, runtime_required_artifacts, execution_targets_required_artifact, artifact_completion_tool_schemas, document_suggestions_event, document_suggestion_quality_error, required_read_tool_choice, required_active_editor_tool_choice, sealed_read_arguments, email_identifier_error, requested_item_limit, contract_item_limit, notes_terminal_response, documents_terminal_response, shell_listing_terminal_response, shell_output_terminal_response, direct_shell_output_request, ui_panel_terminal_response, ui_toggle_state_result, calendar_terminal_response, memory_terminal_response, tasks_terminal_response, task_list_requires_synthesis, skills_terminal_response, cookbook_servers_terminal_response, prior_short_answer_for_no_tool_summary, prior_collection_repeat_answer, prior_failed_operation_answer, prior_cookbook_server_answer, prior_workspace_path_answer, prior_web_source_answer, bounded_web_evidence_answer, inherit_referential_read_arguments, normalized_search_intent, requested_web_source_links, web_source_links, requested_web_link_limit, preserve_requested_web_recency, ground_referenced_note_content, note_search_result_empty, note_referent_error, research_referent_error, private_browser_open_url, private_browser_effective_url, web_fetch_observation_is_boilerplate, broad_current_web_request, record_tool_execution, align_structured_tool_history, provider_request_messages, provider_compatible_tool_choice_request, offered_tool_alias, dependent_write_prerequisite_error, bounded_research_tool_policy, retrieved_source_urls, serialize_required_email_attachment_chain
 from src.tool_capabilities import capabilities_for_tool
 
 
@@ -454,6 +454,53 @@ def test_runtime_required_artifacts_includes_runner_declared_directory():
     ) == ('/tmp_workspace/results',)
 
 
+def test_artifact_completion_schema_binds_single_required_file_without_mutating_source():
+    source = [{
+        'type': 'function',
+        'function': {
+            'name': 'write_file',
+            'description': 'Write a file.',
+            'parameters': {
+                'type': 'object',
+                'properties': {
+                    'path': {'type': 'string'},
+                    'content': {'type': 'string'},
+                },
+                'required': ['path', 'content'],
+            },
+        },
+    }]
+
+    bound = artifact_completion_tool_schemas(
+        source, ('/workspace/output.html',),
+    )
+
+    path_schema = bound[0]['function']['parameters']['properties']['path']
+    assert path_schema['const'] == '/workspace/output.html'
+    assert '/workspace/output.html' in path_schema['description']
+    assert 'const' not in source[0]['function']['parameters']['properties']['path']
+
+
+def test_artifact_completion_schema_does_not_bind_directory_or_multiple_outputs():
+    source = [{
+        'type': 'function',
+        'function': {
+            'name': 'write_file',
+            'parameters': {
+                'type': 'object',
+                'properties': {'path': {'type': 'string'}},
+            },
+        },
+    }]
+
+    assert artifact_completion_tool_schemas(
+        source, ('/workspace/results/',),
+    ) == source
+    assert artifact_completion_tool_schemas(
+        source, ('/workspace/a.txt', '/workspace/b.txt'),
+    ) == source
+
+
 def test_runtime_required_artifacts_does_not_promote_inputs_to_outputs():
     assert runtime_required_artifacts(
         'Read /workspace/input/data.json and write /workspace/results/report.json.',