AI 资讯
Two undocumented bugs in MCP Apps I found building a task panel for Claude
I spent a week building Wingman , an open source MCP server that renders a persistent task panel inline in Claude conversations using MCP Apps (SEP-1865). The spec is solid. The SDK is solid. But I hit two bugs that cost me most of a weekend each, and neither is documented anywhere I could find. Writing them up here in case they save someone else the time. Bug 1: resourceUri has two valid-looking locations, and only one works MCP Apps needs a way to tell the host "render this resource as a UI for this tool call." That pointer lives in _meta.ui.resourceUri . The question is: meta on what? I started with a parameterized resource template, ui://wingman/panel/{plan_name} , registered per plan. That was my first mistake. Parameterized templates get listed under resources/templates/list , not resources/list , and hosts do not prefetch or render anything from the templates list. The fix was straightforward once I found it: register one static resource, ui://wingman/panel , and pass the actual plan data through structuredContent on the tool result instead of baking it into the URI. That fix surfaced the real bug. My show_plan tool was returning a plain Python dict: return { " plan " : plan_data , " _meta " : { " ui " : { " resourceUri " : " ui://wingman/panel " }} } This looks correct. It is not. FastMCP's result conversion takes a returned dict and serializes the whole thing into structuredContent , verbatim, including any _meta key the dict happens to carry. So the actual wire result looked like this: result . structuredContent [ " _meta " ][ " ui " ][ " resourceUri " ] # == "ui://wingman/panel", but wrong place result . meta # None — this is what the host actually reads MCP Apps hosts read resourceUri off the top-level _meta on the CallToolResult , not off whatever ended up inside structuredContent . With that pointer effectively missing, the host had nowhere to bind the iframe. The visible symptom was strange: actions in the UI would update on screen but nothing persist
科技前沿
Meta Pauses Employee-Tracking Program Following Internal Data Leak
The move comes after the company left potentially sensitive data from the initiative exposed internally.
开发者
Valve describes just how brutal RAM negotiations are in 2026
Valve's Steam Machine finally has a price: a whopping $1,049 for the 512GB configuration or $1,349 for the 2TB version. And those are without bundled controllers, which drive up the cost more. The prices are so high in part because Valve isn't subsidizing the hardware, and the company has already indicated that the component crisis […]
产品设计
Man used massage gun on his tired eyeballs. It went as well as you'd expect.
He had retinal tears and bruises from squishing his eyeballs with the gun.
开源项目
Microsoft and Chevron plan one of the largest gas-powered data center projects in US
Microsoft inked a 20-year power purchase agreement with Chevron, locking in decades of carbon emissions from a new natural gas power plant.
AI 资讯
Meta Exposed Data Internally From Its Controversial Employee-Tracking Program
Employees had previously raised concerns about the initiative, which involves collecting workers’ keystroke data to train AI models.
科技前沿
iOS 27 beta 2 is out now, here's what's new
Spoiler: It's more Siri stuff.
科技前沿
Polymarket's viral videos showed people winning big, but the bets were fake
"Winning" bets were made on cloned website and would have lost money, WSJ finds.
AI 资讯
Nvidia wants to cut data center water use, but that’s not the same as fixing AI’s water problem
Nvidia announced a new cooling system that cuts water use inside the data center. But it does nothing to address AI's biggest water use — fossil fuel power plants.
开发者
Microsoft's Secret 90s Weapon That Made Windows Fast
submitted by /u/dukey [link] [留言]
AI 资讯
Valve's Steam Machine ships June 29 for $1,049, but you probably won't be able to buy one yet
Valve says it's using a randomized purchase queue to make the experience "less frustrating and more fair."
AI 资讯
Land your AI agent's email in the inbox, not spam
You give your AI agent a real mailbox, it sends its first batch of email, and half of it lands in spam. The agent did nothing wrong. The domain did — it's new, it has no sending history, and mailbox providers treat an unknown domain that suddenly sends volume the same way they treat a spammer. Deliverability is the work of proving the mail is really yours, sending at a pace providers trust, and watching the signals that say whether recipients want it. An Agent Account sends from a domain you own, so its inbox placement is yours to manage like any other mail from your company. This post is a practical playbook for getting and keeping an agent in the inbox, from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal. I work on the CLI, so the terminal commands below are the ones I reach for when I'm wiring up monitoring. The deliverability checklist Five things decide whether an Agent Account reaches the inbox, and you can act on all of them before sending at volume. Work them in order — authentication first, because nothing else matters if recipient servers can't confirm the mail is yours, then pace and monitoring once mail is flowing. Authenticate the domain with DKIM and SPF as part of domain verification. Set up DMARC so providers know how to treat mail that fails authentication. Warm up a new domain before sending at volume, over roughly four weeks. Monitor bounces and complaints through the deliverability webhooks. Stay under the bounce and complaint thresholds that pause sending. The rest of this post covers each one with the commands and request bodies to wire it up. Authenticate with DKIM and SPF Authentication is the foundation, and for an Agent Account it rides on two records you already publish during domain setup. DKIM adds a cryptographic signature proving the message wasn't altered and really came from your domain; SPF authorizes the sending infrastructure to send on your behalf. Both are verified before a custom domain can host a
AI 资讯
Filter what your AI email agent sends and receives
An AI agent with its own mailbox reacts to whatever lands in it. That's the point, until a spam blast, a mailer-daemon loop, or an auto-reply triggers the agent into answering noise. The same goes the other way: an agent composing mail on its own can address the wrong person, leak to a test domain that slipped into production, or email a competitor because nobody told it not to. A human would catch these. An agent needs guardrails encoded somewhere it can't skip. Agent Accounts ship three admin resources for exactly this: Policies bundle limits and spam settings, Rules match mail on the way in or out and run actions like block or assign_to_folder , and Lists are reusable collections of domains or addresses that rules reference. This post covers all three from two angles: the HTTP API for your backend, and the Nylas CLI for inspecting and managing policies and rules from the terminal. Lists, workspaces, and the rule-evaluations audit log are API-only for now. I work on the CLI, so the terminal commands below are the ones I reach for. How Policies, Rules, and Lists fit together The three resources form a chain, and a workspace ties it to your accounts. A List holds values like domains or addresses. A Rule references lists through the in_list operator and describes conditions and actions. A Policy bundles limits and spam settings. A workspace carries one policy_id plus an array of rule_ids , and every Agent Account in that workspace inherits both. What matters here: you don't attach a policy or rule to an individual grant. You set policy_id and rule_ids on a workspace , and they apply to every account in it. Each application has a default workspace that holds any account you haven't placed elsewhere, so configuring that one workspace covers all your unassigned accounts at once. All three resources are application-scoped — they carry no grant ID in the path, and your API key identifies the application. Resource What it owns How it's referenced List A typed collection of
AI 资讯
Keep your AI agent's email replies in the right thread
An AI agent sends an email, a reply lands three hours later, and the agent has to answer two questions before it can do anything useful: which conversation is this, and what did I last say? Get the first one wrong and the agent's reply shows up in the recipient's inbox as a brand-new message instead of slotting into the existing thread. To the person on the other end, that looks broken — like the agent forgot the conversation it started. Threading is the part of agent email that's easy to get almost right and quietly wrong. The fix lives in a few email headers most developers never touch, and in the Threads API that groups messages into conversations for you. This post walks through both, from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal. I work on the CLI, so the terminal commands below are the ones I reach for when I'm testing a reply loop. The three headers that make threading work Threading runs on three email headers, not on subject lines. Every message carries a Message-ID — a globally unique identifier the sending server stamps on it. When someone replies, their mail client adds In-Reply-To (the Message-ID of the message being answered) and References (the full chain of Message-ID values, oldest to newest). Those two headers are how every mail client decides which messages belong together. Here's what the chain looks like across one exchange. The agent's first message gets a Message-ID ; the reply points back at it; the agent's follow-up references both: # The agent's outbound message Message-ID : <abc123@agents.yourcompany.com> Subject : Following up on your demo request # The recipient's reply Message-ID: <def456@gmail.com> In-Reply-To: <abc123@agents.yourcompany.com> References: <abc123@agents.yourcompany.com> Subject: Re: Following up on your demo request # The agent's follow-up Message-ID: <ghi789@agents.yourcompany.com> In-Reply-To: <def456@gmail.com> References: <abc123@agents.yourcompany.com> <def456@gmail.com> The Ref
AI 资讯
Give your AI agent a real email address on your own domain
Most "AI agent that emails for you" demos point a language model at a human's Gmail inbox over OAuth. That works until the agent needs its own identity: an address people reply to, a calendar that accepts invites, a mailbox your application owns end to end. Borrowing a human's inbox means inheriting their OAuth scopes, their rate limits, and the awkwardness of an agent sending mail as a person who didn't write it. A Nylas Agent Account flips that around. It's a real name@yourcompany.com mailbox that you create and control entirely through the API — it sends, receives, hosts calendar events, and RSVPs, and it's indistinguishable from a human-operated account to anyone on the other end. Under the hood it's just a grant , so the grant_id you get back works with the same grant-scoped endpoints — Messages, Threads, Folders, Drafts, Attachments, Contacts, Calendars, and Events — you've already used for connected accounts, plus the standard webhook triggers. This post is a working tour of provisioning one, from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal and quick experiments. I work on the CLI, so the terminal commands below are the exact ones I reach for. Why an Agent Account beats borrowing a human inbox An Agent Account is a first-class sender, not a delegated one. When the agent owns support@yourcompany.com , people reply to it directly, calendars invite it as a normal participant, and its mail authenticates as coming from you. A few concrete differences from pointing an agent at someone's existing mailbox: No OAuth flow to babysit. Creation needs only an email address on a domain you've registered — there's no refresh token to store or rotate, and the grant rarely expires because there's no OAuth token to refresh. Its own reputation. The account sends on your domain, and a new domain establishes its sender reputation over roughly four weeks of gradual sending. That reputation is yours to protect, not a shared corporate inbox's. Per-t
AI 资讯
3 Tests That Pass in LangFlow But Fail in n8n Production
You built a LangFlow prototype. Every test passed. You exported the flow, dropped it into n8n, and the first production run broke. This is not a bug report. It is a pattern. The three-year SDET who has built LangFlow prototypes but hit mysterious failures when deploying the same logic in n8n production already knows the feeling. The prototype felt solid. The production pipeline felt like a different language. It is not. The difference is execution context. LangFlow runs in a notebook-like environment where state is forgiving and retries are invisible. n8n runs in a workflow engine where every node is a transaction boundary and every failure is final unless you explicitly handle it. Here are the three tests that pass in LangFlow but fail in n8n production, and what they teach about building reliable AI pipelines. Test 1: The "LLM Returns Valid JSON" Test What passes in LangFlow: You send a prompt asking the model to return JSON. The response comes back as a string. You parse it with json.loads() . It works. You move on. What fails in n8n: The model returns a string that starts with a code block. Or a trailing comma. Or a markdown fence. Or a preamble sentence before the JSON. Or nothing at all because the context window was exceeded. Why the difference: LangFlow's Python node silently tolerates malformed output. If json.loads() fails, you see the error in the output panel and fix the prompt. n8n's JSON node does not retry. It does not fall back. It throws a structured error that stops the entire workflow. The fix is not a better prompt. The fix is a validation layer that normalizes LLM output before parsing. import json import re def extract_json ( raw : str ) -> dict : # Strip markdown fences cleaned = re . sub ( r ' ^``` (?:json)?\s* ' , '' , raw . strip ()) cleaned = re . sub ( r ' \s* ```$ ' , '' , cleaned ) # Find the first { and last } start = cleaned . find ( ' { ' ) end = cleaned . rfind ( ' } ' ) if start == - 1 or end == - 1 : raise ValueError ( " No JSON o
AI 资讯
Google DeepMind bets $75M on AI’s future in Hollywood with A24 deal
Google DeepMind and A24 are teaming up to build AI filmmaking tools.
AI 资讯
Tired of Searching for Different Base64 Tools? I Built One Place for Everything
As developers, we've all been there. Q: Need to decode a Base64 string? Open one website. Q: Need to convert an image to Base64? Open another website. Q: Need to validate a Base64 string? Search Google again. Q: Need to compare two Base64 values? Yet another tool. I found myself repeatedly switching between different websites, browser tabs, and terminal commands just to perform simple Base64-related tasks. So I decided to build something that solved this problem for me. The Goal Keep every commonly used Base64 utility in one place and make it work directly in the browser. No installations. No command-line knowledge required. No account creation. Just open the website and use the tool What You'll Find Instead of only providing an encoder and decoder, I wanted to cover the complete Base64 workflow. Some of the available tools include: Base64 Encode / Decode Image to Base64 Audio to Base64 Video to Base64 Base64 Validator Base64 Detector Base64 Compare Base64 Repair Base64 URL Encode Base64 File Decoder CSS Data URI Converter And more are being added regularly. Why I Built It Honestly, this started as a personal productivity project. I was using different Base64 tools almost every week and got tired of bookmarking multiple websites for related tasks. Having everything in one place turned out to be surprisingly useful, so I decided to make it public. Give It a Try https://base64converters.com I'm continuously improving it and would love feedback from fellow developers. Are there any Base64-related tools or workflows you use frequently that should be included?
AI 资讯
How Much Does It Actually Cost to Run a Local LLM? (€ per Million Tokens, Measured)
"It runs on my own GPU, so it's basically free." I believed that until I put a meter on it. So I ran a controlled benchmark on one box — an openSUSE machine with a single RTX 3090 — driving three local models through ollama under an identical fixed workload (256-token generations in a loop for ~4 minutes each), while my open-source dashboard priced every run by the real GPU energy it burned : power sampled from nvidia-smi every 10 s, integrated over each run's exact window, multiplied by my actual day/night tariff. One number per model, in euros per million output tokens. Here's the part that made me re-run it. The tiny gemma3:1b came out at €0.118 / 1M tokens — about 5× cheaper than a hosted Flash-class API (~€0.55). But gemma3:27b 's electricity alone was €0.706 / 1M — more expensive per token than just paying the cloud, and that's before a single cent of the GPU's purchase price. "Local" didn't make it cheaper; it made it cost more and I own the depreciation. The mechanism is one line: each token costs watts ÷ throughput , and a big dense model is both slow and thirsty. A newer mid-size architecture ( gemma4:26b ) bought a lot of that back, landing at €0.272 . The full guide is methodology-first and reproducible end to end — minting an ingest key, the stdlib-only client, the exact ollama loop that reads eval_count / eval_duration for real tokens-per-second, reading each run back priced, and the honest caveats (this is marginal GPU energy only — not capex, idle, or cooling — and the absolute numbers round to fractions of a cent; the shape is the finding). Read the full guide on Medium → https://medium.com/@arsen.apostolov/how-much-does-it-actually-cost-to-run-a-local-llm-per-million-tokens-measured-4a90a7f31a48
AI 资讯
What Prime Day Taught Me About Prompt Engineering
I wanted to get better at prompt engineering. Not the trick-the-robot kind, the boring-but-useful kind: how to ask a model a question so you get an answer you can actually trust. The trouble with practicing is that most tutorials use made-up examples, and it's hard to tell a good answer from a bad one when you don't care about the topic. So I practiced on something I did care about: the deals sitting in my Amazon cart. I had a vacuum I'd been eyeing and a hair styler that was "43% off," and I genuinely wanted to know if those were good prices or just good marketing. The stakes were real, actual money on an actual decision, and that's what made it a good drill. A vague prompt gives you a confident answer, and when you actually care, you can feel that the answer is hollow. What I learned, with the real deals and the actual before-and-after prompts: The trap hiding in every deal Start with the hair styler. The listing said: Shark FlexStyle. Limited time deal. $199.00, 43% savings. List Price: $349.99. My first instinct was the prompt most people write: "Shark FlexStyle $199, 43% off list $349.99, is that a good deal?" This feels reasonable. It is also nearly useless: it lets the model answer the easy question (is 43% off a big discount? sure!) instead of the real one (is $199 actually a good price?). That $349.99 list price is a marketing anchor. A lazy prompt accepts it, and so you get a lazy "yes, great deal!" back. The fix was re-framing this: Act as a pricing analyst. I don't care whether $199 looks like a discount off list. I care whether $199 is a genuinely good price for the Shark FlexStyle right now. Before concluding, work through: (1) the actual street price over the last 6-12 months, (2) how often it drops to or below $199, (3) the real discount vs. its typical selling price, not vs. list. Cite a source and date for each price, or mark it unverified. Same question, completely different answer. What the assistant came back with, in its own telling: $199 is a