mcpwright-core 0.1.0

Shared runtime toolkit for the mcpwright suite of MCP servers — async HTTP client, cache, and server helpers.

mcpwright-core

The shared runtime toolkit for the mcpwright suite of MCP servers. Not a server itself — a small library the suite's servers (edgar, census, soi, …) depend on so they don't each re-implement the same plumbing.

Status: extracted once three servers existed and the seams were clear ("wait for two, then DRY"). Composable pieces — import what you need; no server uses all of it.

What's in it

Import	What it is
AsyncHttpClient	Async httpx base: descriptive User-Agent, retry + exponential backoff on transient failures (429 / 5xx / network), optional throttling, and a streaming download_to(url, path) for large files. Subclass it and add your endpoint methods.
RateLimiter	Serializes requests to a minimum spacing (RateLimiter.per_second(8)), for services with a fair-access policy like the SEC.
TTLCache	In-memory cache with per-entry TTL + a byte budget (LRU eviction). For servers that make live calls; bulk-download servers don't need it.
READ_ONLY	The ToolAnnotations(readOnlyHint=True, openWorldHint=True) every suite tool carries.
app_context(ctx, AppContext)	Pulls the lifespan-managed app context out of an MCP request Context.
McpwrightError / HttpError	The error hierarchy; each server's error type derives from these.

Usage

from mcpwright_core import AsyncHttpClient, RateLimiter, HttpError

class MyError(HttpError):
    pass

class MyClient(AsyncHttpClient):
    USER_AGENT = "my-mcp (https://github.com/mcpwright/my-mcp)"

    def __init__(self) -> None:
        super().__init__(error_cls=MyError, rate_limiter=RateLimiter.per_second(8))

    async def widget(self, widget_id: str) -> dict:
        return await self.get_json(f"https://api.example.com/widgets/{widget_id}")

Install

uv add mcpwright-core          # in a suite server's project

Servers pin a compatible range, e.g. mcpwright-core>=0.1,<0.2.

Develop

uv sync
uv run ruff check src/ && uv run ruff format --check src/
uv run mypy
uv run pytest

Built to the suite engineering standard: ruff + mypy (strict-ish) + pytest + pre-commit, CI on every PR, branch-protected main. Part of the mcpwright suite — built by Devender Gollapally.