说明书该做成 MCP 资源，还是查询工具？

"""Offline fixtures inspired by MCP 2025-11-25; no MCP server or LLM."""
from copy import deepcopy

guide = "study://guide"
report = "study://report/7"
store = {
    guide: {"uri": guide, "version": "v1", "text": "Bring a notebook."},
    report: {"uri": report, "version": "v1", "text": "There are two open tasks."},
}
catalog = [{"uri": guide, "name": "Study guide"}]
# Model a tool result containing a link that is NOT in resources/list.
tool_result = {"content": [{"type": "resource_link", "uri": report,
                            "name": "Task report"}]}
allowed = {guide, report}  # Teaching policy, not a real authorization service.
cache, stale = {}, set()


def read(uri):
    if uri not in allowed:
        raise PermissionError("uri denied")
    cache[uri] = deepcopy(store[uri])
    stale.discard(uri)


def assemble(uris, byte_budget=200):
    if any(uri not in allowed for uri in uris):
        raise PermissionError("uri denied")
    if any(uri not in cache or uri in stale for uri in uris):
        raise ValueError("read current content first")
    rows = [cache[uri] for uri in uris]
    if sum(len(row["text"].encode("utf-8")) for row in rows) > byte_budget:
        raise ValueError("context budget exceeded")
    return deepcopy(rows)  # Preserve what THIS simulated turn actually received.


assert not cache  # Discovery alone has not read any contents.
assert report not in {item["uri"] for item in catalog}
read(guide)
read(tool_result["content"][0]["uri"])
turn1 = assemble([guide, report])
print("turn1:", ",".join(row["version"] for row in turn1))

store[guide] = {"uri": guide, "version": "v2", "text": "Bring a laptop."}
notification = {"method": "notifications/resources/updated",
                "params": {"uri": guide}}
stale.add(notification["params"]["uri"])
assert "text" not in notification["params"]
assert turn1[0]["version"] == "v1"
try:
    assemble([guide])
except ValueError:
    print("after_notice: needs_read")
else:
    raise AssertionError("stale cached content was accepted")

read(guide)
turn2 = assemble([guide, report])
assert turn1[0]["version"] == "v1" and turn2[0]["version"] == "v2"
print("turn2:", ",".join(row["version"] for row in turn2))
cache[report]["text"] = "Changed only inside the local cache."
assert turn1[1]["text"] == "There are two open tasks."
assert turn2[1]["text"] == "There are two open tasks."
for uri in ["study://private", "https://untrusted.invalid/data"]:
    try:
        read(uri)
    except PermissionError:
        pass
    else:
        raise AssertionError("unknown URI must not be read")
try:
    assemble([guide], byte_budget=0)
except ValueError:
    pass
else:
    raise AssertionError("budget must be enforced")
print("PASS: discovery, unlisted link, snapshot, notice, permission, budget")