Implemented the next parity slice: prompt-budget preflight and context collapse.

Core changes:

  - Added claw-code/src/token_budget.py for projected prompt size, chat-framing overhead, output reserve, and soft/hard input limits.
  - Wired preflight prompt-length validation and auto-compact/context collapse into claw-code/src/agent_runtime.py.
  - Extended claw-code/src/compact.py so compaction reports usage back to the runtime.
  - Added inspection surfaces in claw-code/src/agent_slash_commands.py and claw-code/src/main.py:
      - /token-budget and /budget
      - token-budget
  - Hardened claw-code/src/tokenizer_runtime.py so arbitrary simple model names fall back cleanly instead of trying a slow Transformers
    lookup.
  - Exported the new helpers in claw-code/src/__init__.py.

  Docs and tracking:

  - Updated claw-code/PARITY_CHECKLIST.md to mark prompt-length validation, token-budget calculation, and auto-compact/context collapse as
    done.
  - Updated claw-code/README.md and claw-code/TESTING_GUIDE.md with the new commands and behavior.

  Tests:

  - Added claw-code/tests/test_token_budget.py.
  - Updated claw-code/tests/test_agent_runtime.py, claw-code/tests/test_agent_slash_commands.py, claw-code/tests/test_main.py, and claw-code/
    tests/test_agent_context_usage.py.
  - Verified with:
      - /data/fs201059/aa17626/miniconda3/bin/python3 -m compileall src tests
      - /data/fs201059/aa17626/miniconda3/bin/python3 -m unittest -v tests.test_token_budget
        tests.test_agent_runtime.AgentRuntimeTests.test_agent_rejects_prompt_before_backend_when_preflight_input_budget_is_exceeded
        tests.test_agent_runtime.AgentRuntimeTests.test_agent_auto_compacts_context_before_next_model_call tests.test_agent_slash_commands
        tests.test_main tests.test_compact tests.test_tokenizer_runtime tests.test_agent_context_usage
      - Result: 71 tests, OK

src/agent_tools.py

@@ -20,6 +20,7 @@ if TYPE_CHECKING:
     from .account_runtime import AccountRuntime
     from .ask_user_runtime import AskUserRuntime
     from .config_runtime import ConfigRuntime
+    from .lsp_runtime import LSPRuntime
     from .mcp_runtime import MCPRuntime
     from .plan_runtime import PlanRuntime
     from .remote_runtime import RemoteRuntime
@@ -51,6 +52,7 @@ class ToolExecutionContext:
     account_runtime: 'AccountRuntime | None' = None
     ask_user_runtime: 'AskUserRuntime | None' = None
     config_runtime: 'ConfigRuntime | None' = None
+    lsp_runtime: 'LSPRuntime | None' = None
     mcp_runtime: 'MCPRuntime | None' = None
     remote_runtime: 'RemoteRuntime | None' = None
     remote_trigger_runtime: 'RemoteTriggerRuntime | None' = None
@@ -126,6 +128,7 @@ def build_tool_context(
     account_runtime: 'AccountRuntime | None' = None,
     ask_user_runtime: 'AskUserRuntime | None' = None,
     config_runtime: 'ConfigRuntime | None' = None,
+    lsp_runtime: 'LSPRuntime | None' = None,
     mcp_runtime: 'MCPRuntime | None' = None,
     remote_runtime: 'RemoteRuntime | None' = None,
     remote_trigger_runtime: 'RemoteTriggerRuntime | None' = None,
@@ -146,6 +149,7 @@ def build_tool_context(
         account_runtime=account_runtime,
         ask_user_runtime=ask_user_runtime,
         config_runtime=config_runtime,
+        lsp_runtime=lsp_runtime,
         mcp_runtime=mcp_runtime,
         remote_runtime=remote_runtime,
         remote_trigger_runtime=remote_trigger_runtime,
@@ -313,6 +317,36 @@ def default_tool_registry() -> dict[str, AgentTool]:
             },
             handler=_run_bash,
         ),
+        AgentTool(
+            name='LSP',
+            description='Use local LSP-style code intelligence for definitions, references, hover, symbols, and call hierarchy.',
+            parameters={
+                'type': 'object',
+                'properties': {
+                    'operation': {
+                        'type': 'string',
+                        'enum': [
+                            'goToDefinition',
+                            'findReferences',
+                            'hover',
+                            'documentSymbol',
+                            'workspaceSymbol',
+                            'goToImplementation',
+                            'prepareCallHierarchy',
+                            'incomingCalls',
+                            'outgoingCalls',
+                        ],
+                    },
+                    'file_path': {'type': 'string'},
+                    'line': {'type': 'integer', 'minimum': 1},
+                    'character': {'type': 'integer', 'minimum': 1},
+                    'query': {'type': 'string'},
+                    'max_results': {'type': 'integer', 'minimum': 1, 'maximum': 200},
+                },
+                'required': ['operation', 'file_path', 'line', 'character'],
+            },
+            handler=_lsp_query,
+        ),
         AgentTool(
             name='web_fetch',
             description='Fetch a text resource from http, https, or file URLs and return a truncated text response.',
@@ -2729,6 +2763,42 @@ def _delegate_agent_placeholder(
     )
 
 
+def _lsp_query(arguments: dict[str, Any], context: ToolExecutionContext):
+    runtime = _require_lsp_runtime(context)
+    operation = _require_string(arguments, 'operation')
+    file_path = _require_string(arguments, 'file_path')
+    line = _coerce_int(arguments, 'line', 1)
+    character = _coerce_int(arguments, 'character', 1)
+    query = arguments.get('query')
+    if query is not None and not isinstance(query, str):
+        raise ToolExecutionError('query must be a string')
+    max_results = _coerce_int(arguments, 'max_results', 50)
+    try:
+        result = runtime.query(
+            operation,
+            file_path=file_path,
+            line=line,
+            character=character,
+            query=query,
+            max_results=max_results,
+        )
+    except KeyError as exc:
+        raise ToolExecutionError(str(exc)) from exc
+    return (
+        result.content,
+        {
+            'action': 'lsp_query',
+            'operation': result.operation,
+            'file_path': file_path,
+            'line': line,
+            'character': character,
+            'result_count': result.result_count,
+            'file_count': result.file_count,
+            'symbol_name': result.symbol_name,
+        },
+    )
+
+
 def _require_account_runtime(context: ToolExecutionContext):
     if context.account_runtime is None:
         raise ToolExecutionError('No local account runtime is available.')
@@ -2756,6 +2826,14 @@ def _require_config_runtime(context: ToolExecutionContext):
     return context.config_runtime
 
 
+def _require_lsp_runtime(context: ToolExecutionContext):
+    if context.lsp_runtime is None or not context.lsp_runtime.has_lsp_support():
+        raise ToolExecutionError(
+            'No local LSP runtime is available. Add supported source files to the workspace or a .claw-lsp.json manifest.'
+        )
+    return context.lsp_runtime
+
+
 def _require_mcp_runtime(context: ToolExecutionContext):
     if (
         context.mcp_runtime is None