Forward ghidra()/ghidra_tools() to the shared read-only Ghidra MCP server

Every agent reaches GhidrAssistMCP through Harbor's own MCP server, so no
per-host configuration is needed. Configured by ghidra_url in [reverse];
long decompiles are polled; also 'harbor re ghidra <tool> <json>'.

harbor/cli.py

@@ -255,8 +255,9 @@ def build_parser():
     p = sub.add_parser("who", help="who has worked on a scope (notes, reviews, claims, messages)")
     p.add_argument("scope")
     p = sub.add_parser("re", help="reverse-engineering lookups from the project's image and annotations")
-    p.add_argument("action", choices=["disasm", "xrefs", "bytes", "lookup"])
-    p.add_argument("target", help="an address (0x4AD850) or a name")
+    p.add_argument("action", choices=["disasm", "xrefs", "bytes", "lookup", "ghidra", "ghidra-tools"])
+    p.add_argument("target", nargs="?", default="", help="an address (0x4AD850) or a name; for ghidra, the tool")
+    p.add_argument("arguments", nargs="?", default="{}", help="ghidra: the tool's arguments as JSON")
     p.add_argument("--max-bytes", type=int, dest="max_bytes")
     p.add_argument("--count", type=int, default=16)
     p.add_argument("--as", dest="as_type", default="hex", choices=["hex", "int32", "uint32", "float", "double", "string"])
@@ -673,9 +674,15 @@ def main(argv=None):
         r = harbor.summarize(who(), args.thread, text)
         out(r, f"summary #{r['id']} pinned to {r['thread']}")
     elif cmd == "re":
-        from .reverse import Reverse
-        r = Reverse(harbor.project.reverse)
-        if args.action == "disasm":
+        from .reverse import Ghidra, Reverse
+        r = None if args.action.startswith("ghidra") else Reverse(harbor.project.reverse)
+        if args.action == "ghidra-tools":
+            res = Ghidra(harbor.project.reverse).tools()
+            out(res, "\n".join(f"{t['name']:<26} {t['description'].splitlines()[0][:90]}" for t in res))
+        elif args.action == "ghidra":
+            text = Ghidra(harbor.project.reverse).call(args.target, json.loads(args.arguments))
+            out({"result": text}, text)
+        elif args.action == "disasm":
             text = r.disassemble(args.target, args.max_bytes)
             out({"disassembly": text}, text)
         elif args.action == "xrefs":

harbor/mcp_server.py

@@ -35,7 +35,9 @@ review queue, presence and stop flags. Protocol:
 9. A correction is send(..., corrects=<id of your earlier message>).
 10. Before your session ends or your allowance runs out, write handoff(): finished, in flight, next.
 11. To read the original machine code use re_disassemble, re_xrefs, re_bytes and re_lookup: they read the project's
-    own image with the team's current names, so do not write your own disassembler or offset maths."""
+    own image with the team's current names, so do not write your own disassembler or offset maths.
+    For Ghidra's view (decompiler, p-code, stack frames, struct field references, types) use ghidra_tools() once,
+    then ghidra(tool, arguments): one shared read-only Ghidra session holding the team's annotations."""
 
 KindName = Literal["note", "question", "answer", "request", "finding", "retraction", "decision", "status", "handoff"]
 Importance = Literal["normal", "high", "urgent"]
@@ -484,6 +486,37 @@ def re_lookup(target: str) -> dict:
     return _re(lambda r: r.lookup(target))
 
 
+_ghidra = {}
+
+
+def _gh(fn):
+    try:
+        h = harbor()
+        g = _ghidra.get(h.project.name)
+        if g is None:
+            from .reverse import Ghidra
+            g = _ghidra[h.project.name] = Ghidra(h.project.reverse)
+        return fn(g)
+    except (HarborError, projects.ProjectError) as error:
+        raise ToolError(str(error)) from None
+
+
+@mcp.tool()
+def ghidra_tools() -> list:
+    """The tools of the team's shared Ghidra session (GhidrAssistMCP, read-only, the curated project with every
+    applied annotation): name, description and arguments. Call them with ghidra(tool, arguments)."""
+    return _gh(lambda g: g.tools())
+
+
+@mcp.tool()
+def ghidra(tool: str, arguments: dict | None = None) -> str:
+    """Run one tool in the shared read-only Ghidra session, e.g. ghidra('get_code', {'function': 'GetFogLevel',
+    'format': 'decompiler'}), ghidra('get_function_stack_layout', {'function_name_or_address': '0x4ADC70'}),
+    ghidra('struct', {'action': 'field_xrefs', ...}). Long decompiles are waited for. Renames, retypes and other
+    changes are refused: names and types change through annotations/ and land on main."""
+    return _gh(lambda g: g.call(tool, arguments or {}))
+
+
 def _report_in():
     """Tell Harbor this agent's app has its tools running: at start, then every 5 minutes while the app keeps the
     server open (updates the connection only, not the agent's last-seen time)."""

harbor/reverse.py

@@ -276,3 +276,83 @@ class Reverse:
                 out["file"] = {"path": str(path.relative_to(self.src.parent)).replace(os.sep, "/"), "status": status}
                 break
         return out
+
+
+class Ghidra:
+    """A small client for the shared, read-only Ghidra MCP server (GhidrAssistMCP over streamable HTTP), so every
+    agent reaches Ghidra through Harbor's own tools. Configured by `ghidra_url` in the [reverse] table."""
+
+    def __init__(self, config):
+        self.url = (config or {}).get("ghidra_url")
+        if not self.url:
+            raise HarborError("this project has no ghidra_url in its [reverse] table")
+        self.session = None
+        self.counter = 0
+
+    def _post(self, method, params=None, notify=False, timeout=120):
+        import urllib.error
+        import urllib.request
+        body = {"jsonrpc": "2.0", "method": method, **({"params": params} if params is not None else {})}
+        if not notify:
+            self.counter += 1
+            body["id"] = self.counter
+        headers = {"Content-Type": "application/json", "Accept": "application/json, text/event-stream"}
+        if self.session:
+            headers["Mcp-Session-Id"] = self.session
+        request = urllib.request.Request(self.url, json.dumps(body).encode(), headers=headers, method="POST")
+        try:
+            with urllib.request.urlopen(request, timeout=timeout) as response:
+                self.session = response.headers.get("Mcp-Session-Id") or self.session
+                text = response.read().decode("utf-8", "replace")
+        except urllib.error.HTTPError as error:
+            if error.code in (400, 404) and self.session and method != "initialize":
+                self.session = None                       # the server restarted: start a new session once
+                self._initialize()
+                return self._post(method, params, notify, timeout)
+            raise HarborError(f"the Ghidra server answered {error.code}: {error.read()[:300]!r}") from None
+        except OSError as error:
+            raise HarborError(f"the shared Ghidra server at {self.url} is not answering ({error}); start it with "
+                              "R:/Workspace/Tools/re/ghidra-serve.ps1, or ask the coordinator") from None
+        if notify or not text.strip():
+            return None
+        if not text.lstrip().startswith("{"):
+            text = next((line[5:] for line in text.splitlines() if line.startswith("data:")), "{}")
+        answer = json.loads(text)
+        if "error" in answer:
+            raise HarborError(f"Ghidra: {answer['error'].get('message', answer['error'])}")
+        return answer.get("result")
+
+    def _initialize(self):
+        self._post("initialize", {"protocolVersion": "2025-06-18", "capabilities": {},
+                                  "clientInfo": {"name": "harbor", "version": "2"}})
+        self._post("notifications/initialized", notify=True)
+
+    def _ensure(self):
+        if not self.session:
+            self._initialize()
+
+    def tools(self):
+        """The server's tools: name, description and argument schema."""
+        self._ensure()
+        return [{"name": t["name"], "description": t.get("description", ""),
+                 "arguments": (t.get("inputSchema") or {}).get("properties", {}),
+                 "required": (t.get("inputSchema") or {}).get("required", [])}
+                for t in self._post("tools/list")["tools"]]
+
+    def call(self, tool, arguments=None, wait=180):
+        """Call one tool; long-running ones (the decompiler) are polled until they finish or `wait` seconds pass."""
+        import time
+        self._ensure()
+        result = self._post("tools/call", {"name": tool, "arguments": arguments or {}}, timeout=wait + 30)
+        text = "\n".join(c.get("text", "") for c in result.get("content", []) if isinstance(c, dict))
+        task = re.search(r"Task ID: ([0-9a-f-]{36})", text) if "async execution" in text else None
+        deadline = time.monotonic() + wait
+        while task and time.monotonic() < deadline:
+            time.sleep(1)
+            result = self._post("tools/call", {"name": "get_task_status", "arguments": {"task_id": task.group(1)}})
+            text = "\n".join(c.get("text", "") for c in result.get("content", []) if isinstance(c, dict))
+            if not re.search(r"Status: (RUNNING|PENDING|QUEUED)", text):
+                break
+        if result.get("isError"):
+            raise HarborError(text.strip() or f"Ghidra refused {tool}")
+        return re.sub(r"^\[Context\] Operating on: [^\n]*\n+", "", text)