Prompt Tape seals a prompt, system prompt, or long instruction into a one-time URL. The link returns plain text any AI agent can fetch and run; humans can read it too.

How do I use Prompt Tape with an AI agent?

Add the remote MCP endpoint https://n78.xyz/mcp to Claude, Cursor, or any MCP client, then ask your agent to seal text into a tape. Or POST to https://n78.xyz/api/capsules and share the returned URL.

How long does a prompt tape last?

Up to 7 days — 1 hour, 1 day, or 7 days. Each tape carries a delete key so you can remove it anytime.

USING · GET STARTED

Seal a prompt into a tape — for any agent

Prompt Tape = seal a prompt / system prompt / long instruction into a one-time URL. /c/{slug} returns plain text any agent can fetch and run; humans can read it too. Lasts up to 7 days, comes with a delete key.

n78.xyz/mcp · live Open source · MIT

The gist

Got something good? Seal it, hand it over.

A promptyour tuned prompt / long instruction

Seal itcreate_prompt_tape

A linkn78.xyz/c/…

https://scheme n78.xyzdomain /c/path okIdDdhUthe code

↑ share just this

A tape link looks like this. Scheme, domain, and path are fixed — what actually identifies the tape is the last little chunk: the code. So skip the full link; share just that code, and any AI with the skill can still fetch it.

One link, two faces

/c/{code} for AI · fetch and run

/view/{code} for people · read, share (WeChat / Feishu / RED)

Gone once it expires, or when you kill it with the delete key.

Three ways in

Pick the one that fits what you've got.

Remote MCP

Recommended · zero install

Add this endpoint to any MCP client (Claude, Cursor, …) — one URL, done. Then tell your agent “seal this into a tape” and it calls the tool and hands back a link.

// mcp config for Claude / Cursor
{
  "mcpServers": {
    "prompt-tape": { "url": "https://n78.xyz/mcp" }
  }
}

HTTP API

live

Skip MCP, hit the API. One POST and you're done — url is for the agent, view_url for humans, agent_text is a ready-made line.

curl -X POST https://n78.xyz/api/capsules \
  -H 'content-type: application/json' \
  -d '{"content":"review my current repo and report issues","source":"api"}'

Skill package

skills/prompt-tape

A SKILL.md teaches the agent to fall back in three layers: call MCP if it can; else the bundled client.js over HTTP; else guide the user to n78.xyz and draft a share post. Install it on any skill-capable platform. Source in the repo — skills/prompt-tape/。

Three tools

What the MCP endpoint does.

Tool	Args	Returns
create_prompt_tape	content · title? · ttl_seconds?	view_url · raw_url · code · code_share_text · delete_token · expires_at · agent_text
read_prompt_tape	target (code or URL)	the tape's text (or tells you it's gone/invalid)
delete_prompt_tape	slug · delete_token	deleted

Reverse · no downrank

Share the code, not the link

Reverse works too: the URL suffix is the tape’s "code". Share the bare code, tell an AI (with the skill) "read tape XXXX", and it fetches the text and runs it. Sharing bare codes dodges the link-downranking some platforms do — use the code_share_text create returns.

A full example

Create → share / let agents fetch → delete.

// 1. agent calls create, gets back:
{
  "view_url":        "https://n78.xyz/view/okIdDdhU",  // for humans
  "raw_url":         "https://n78.xyz/c/okIdDdhU",     // for agents to fetch
  "code":            "okIdDdhU",                       // the capsule code — shareable on its own
  "code_share_text": "…read prompt tape okIdDdhU…",        // code-only share line (no URL, dodges downranking)
  "delete_token":    "…",                            // keep private
  "agent_text":      "… https://n78.xyz/c/okIdDdhU"
}

// 2. downstream fetches raw_url (or just the code via read_prompt_tape), runs the text
curl https://n78.xyz/c/okIdDdhU

// 3. done with it? delete with the key
curl -X POST https://n78.xyz/api/capsules/okIdDdhU/delete \
  -d '{"delete_token":"…"}'

Limits

A few lines not to cross.

Content ≤ 16KB. Over that → 413. Tapes hold prompts, not files.
Lifespan ≤ 7 days (7 by default; pass ttl_seconds to shorten). Auto-expires.
Keep the delete key private. Don't put it in a public post — anyone with it can delete.
Create limit: 10/min per IP. Plenty for normal use.
Public and anonymous: no accounts, no login. Tapes are temporary, public, fetchable.

Go make a tape TRY IT