# PaperAgent — Send Physical Mail (remote · paperagent.dev)

Mail one-off USPS letters from ChatGPT or Claude after you approve the preview and price. US only.

- Trust score: 83/100 (high trust)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-25

## Components

- remote · `paperagent.dev`: 83/100 (this document), [markdown](https://verifymcp.io/servers/dev-paperagent-letters/paperagent.md), [page](https://verifymcp.io/servers/dev-paperagent-letters/paperagent)

## Channel facts

- Endpoint: `https://paperagent.dev/mcp`
- Transports: `streamable-http`
- Auth: `required`
- Version: `0.1.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-10-25.

- **Endpoint Security**: 95/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation is enforced on tool calls, advertised via RFC 9728 protected-resource metadata. Discovery is public, which costs nothing: no tool can be invoked without a token.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC is configured correctly; the domain's records validate against the full chain to the root.
  - The authorisation server supports Client ID Metadata Documents, the current MCP client-registration mechanism.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 80/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1930 tokens (~160/item across 12 items; 8 tools + 4 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 20/100
  - Stability observed for 6 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 96/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 85% of tool parameters carry a description.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.
  - An AI judge read all 10 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.
  - Supports UI / widget rendering.

## Install

### How do I install the PaperAgent — Send Physical Mail MCP server?

PaperAgent — Send Physical Mail is a hosted endpoint at https://paperagent.dev/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http dev-paperagent-letters 'https://paperagent.dev/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "dev-paperagent-letters": {
      "url": "https://paperagent.dev/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "dev-paperagent-letters": {
      "type": "http",
      "url": "https://paperagent.dev/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.dev-paperagent-letters]
url = "https://paperagent.dev/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "dev-paperagent-letters": {
      "type": "remote",
      "url": "https://paperagent.dev/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add dev-paperagent-letters --url 'https://paperagent.dev/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  dev-paperagent-letters:
    url: "https://paperagent.dev/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "dev-paperagent-letters": {
      "Transport": "http",
      "Url": "https://paperagent.dev/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add dev-paperagent-letters -t streamable-http -u 'https://paperagent.dev/mcp'
```

### Other

```json
{
  "mcpServers": {
    "dev-paperagent-letters": {
      "type": "http",
      "url": "https://paperagent.dev/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-10-25 (score 83, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-23 (score 82, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-20 (score 81, +1)

- [functional improvement] Stability: unverified → 0.03

### 2026-10-19 (score 80)

First indexed and scored.

## MCP tools (8)

### `get_pricing` (~110 tokens)

Get Letter Pricing

Return the published price list for mailing physical letters through USPS: the products on sale, what each one costs, how many pages it covers, and when sales tax applies. Amounts are in US cents. Every letter is one of these prices — there is no volume discount, no per-page charge and no colour printing — so quote the tier total and say New York sales tax is added, whatever the destination. Call this before telling a user what a letter will cost. This creates nothing and mails nothing.

Output parameters:

- `add_ons` (array)
- `country` (string)
- `currency` (string)
- `effective_from` (string)
- `page_rules` (object)
- `tax` (object)
- `tiers` (array)
- `version` (string)
- `volume_pricing` (object)

### `validate_address` (~127 tokens)

Validate a US Postal Address

Check a US postal address and return it in the normalized form the envelope will be printed with, plus any warnings. The address is checked against the Google Address Validation service, which receives the address and nothing else. Use this before create_draft whenever the address came from a person rather than from an earlier tool result. Requires a complete street address: this does not look up, append or find an address from a name, and it does not handle addresses outside the United States. This creates nothing and mails nothing.

Input parameters:

- `address` (object, required): A complete US postal address. US domestic addresses only.

Output parameters:

- `address`: Null when USPS could not answer about the address at all.
- `corrections` (array): What USPS changed. Tell the user if it corrected anything material.
- `deliverable` (boolean)
- `message` (string): The sentence to act on. Read it before answering the user.

### `create_draft` (~459 tokens)

Create a Letter Draft

Create a draft of a physical letter to be printed on paper and mailed through USPS, and return its draft_id, page count and total price. A letter is at most 6 printed pages, at the same price whatever its length: up to 3 pages print one-sided, 4 to 6 print on both sides. Write the body to fit, or split a longer document into two letters, because a body that renders to 7 or more pages is refused rather than trimmed. This is NOT email, fax or text message — nothing reaches the recipient electronically, and the only way this letter arrives is on paper in an envelope. The body is plain text or Markdown. The draft freezes the content and the price for 24 hours and costs nothing; no paper is printed and no postage is bought until send_letter is called. US domestic addresses only. Call preview_draft next so the user can see the letter and the total.

Input parameters:

- `body_file` (object): A file the user attached, as the host delivers it. Not accepted yet — create_draft refuses an attachment and asks for the letter as body_markdown text.
- `body_markdown` (string, required): The text of the letter, as plain text or Markdown. It must render to 6 printed pages or fewer — roughly 2,400 words of body text.
- `colour` (boolean): Omit this. The current price card prints every letter black & white, so passing true is refused rather than billed — call get_pricing for what it does sell. The field remains because letters priced o…
- `from_address_id` (string): Omit this. The account's own verified return address is used by default; only pass an id the account holder gave you.
- `tier` (string): Defaults to standard. Call get_pricing first and pass a tier it lists: standard is a plain First-Class letter. certified, certified_err, proof_of_mailing and registered are other products the current…
- `to` (object, required): Who the letter is mailed to.

Output parameters:

- `draft_id` (string): Pass this to preview_draft, update_draft and send_letter.
- `expires_at` (string): ISO 8601 instant the draft is deleted. Nothing is charged if it expires.
- `included_pages` (integer): Printed pages the headline price covers. This draft is priced at that total up to this many pages.
- `note` (string): The next call to make. Read it before answering the user.
- `page_count` (integer): Printed pages, as counted by the renderer. Never more than 6 — a longer body is refused.
- `quote` (object): A priced letter. State total.display to the user before sending, and pass total.amount_cents as confirm_total_cents.
- `sheet_count` (integer): Sheets of paper this letter is printed on: one page per sheet, one side each, up to 3 pages; a letter of 4 to 6 pages is printed on both sides, so it is never more than 3 sheets.
- `tier` (string): The product this draft is priced as, as passed to create_draft or update_draft.
- `tier_title` (string): What the price card in force calls that product, such as Standard. Use this name when you tell the user what they are buying.

### `update_draft` (~286 tokens)

Update a Letter Draft

Change the recipient, body, tier or colour of a draft that has not been sent, and re-price it. Returns a new page count and a new quote, so the previous total is void — state the new total to the user before sending. The 6-printed-page maximum applies to the new body as well: a replacement that renders to 7 or more pages is refused and the draft is left as it was. This creates nothing and mails nothing.

Input parameters:

- `body_markdown` (string): Replaces the whole letter text. It must render to 6 printed pages or fewer — roughly 2,400 words of body text.
- `colour` (boolean): Omit this. The current price card prints black & white only; true is refused.
- `draft_id` (string, required): The draft_id returned by create_draft.
- `from_address_id` (string)
- `tier` (string): Which product to buy. Call get_pricing first and pass a tier it lists: standard is a plain First-Class letter. certified, certified_err, proof_of_mailing and registered are other products the current…
- `to` (object): A complete US postal address. US domestic addresses only.

Output parameters:

- `draft_id` (string): Pass this to preview_draft, update_draft and send_letter.
- `expires_at` (string): ISO 8601 instant the draft is deleted. Nothing is charged if it expires.
- `included_pages` (integer): Printed pages the headline price covers. This draft is priced at that total up to this many pages.
- `note` (string): The next call to make. Read it before answering the user.
- `page_count` (integer): Printed pages, as counted by the renderer. Never more than 6 — a longer body is refused.
- `quote` (object): A priced letter. State total.display to the user before sending, and pass total.amount_cents as confirm_total_cents.
- `sheet_count` (integer): Sheets of paper this letter is printed on: one page per sheet, one side each, up to 3 pages; a letter of 4 to 6 pages is printed on both sides, so it is never more than 3 sheets.
- `tier` (string): The product this draft is priced as, as passed to create_draft or update_draft.
- `tier_title` (string): What the price card in force calls that product, such as Standard. Use this name when you tell the user what they are buying.

### `preview_draft` (~97 tokens)

Preview a Letter Draft

Return a link to the rendered PDF of a draft together with its page count and current total price. Refreshes the stored price quote when pricing has changed. Use this to show the user exactly what will be printed and exactly what it costs before calling send_letter. The total in the response is the number send_letter requires as confirm_total_cents. This does not create an order or mail a letter.

Input parameters:

- `draft_id` (string, required)

Output parameters:

- `draft_id` (string)
- `expires_at` (string)
- `included_pages` (integer): Printed pages the headline price covers. This draft is priced at that total up to this many pages.
- `page_count` (integer)
- `preview_url` (string): A time-limited link to the exact PDF that will be printed. Give it to the user; it dies with the draft.
- `quote` (object): A priced letter. State total.display to the user before sending, and pass total.amount_cents as confirm_total_cents.
- `requirements` (array): What the user is agreeing to: how USPS requires the envelope to be printed, and what this particular letter is. State these to the user before calling send_letter.
- `tier` (string): The product this draft is priced as, as passed to create_draft.
- `tier_title` (string): What the price card in force calls that product, such as Standard. Use this name when you tell the user what they are buying.

### `send_letter` (~232 tokens)

Send a Physical Letter (USPS)

Create an order for a real, physical letter through the United States Postal Service. It returns a payment link; no paper is printed, postage is bought, or letter is mailed until payment completes. Use this whenever the user asks to mail, post, send by post, or physically send a letter, notice, or document to a street address. This is NOT email — use an email tool for email. US domestic addresses only. Requires a draft_id from create_draft and confirm_total_cents matching the current quote. The letter becomes irreversible once we print it.

Input parameters:

- `confirm_total_cents` (integer, required): The exact total.amount_cents from the current quote, including sales tax. Say the total out loud to the user first; if it does not match the live quote this call fails and no letter is sent.
- `draft_id` (string, required): The draft_id returned by create_draft or preview_draft.
- `idempotency_key` (string, required): A key you generate once for this send. Retrying with the same draft_id and the same key returns the original letter instead of mailing a second one.

Output parameters:

- `checkout_url`: Give this link to the user. The letter is mailed once payment completes. Null when this call replayed a send whose payment has already completed — there is then nothing to pay and nothing to relay.
- `letter_id` (string)
- `mail_date_estimate` (string): The calendar date (YYYY-MM-DD, New York time) this piece goes to USPS if the payment lands before that day’s 14:30 cutoff.
- `message` (string): What to tell the user. Relay the link and the total.
- `order_id` (string)
- `quote` (object): A priced letter. State total.display to the user before sending, and pass total.amount_cents as confirm_total_cents.
- `status` (string): The current letter status, including on an idempotent replay. Nothing is printed or mailed until payment completes.

### `get_letter_status` (~90 tokens)

Get Letter Status

Return the current state of one letter: where it is, the date it goes to USPS, and the estimated delivery date. USPS does not scan plain First-Class letters at delivery, so a Standard letter ends at an expected delivery date and never reports delivery — do not tell the user a letter arrived unless the status itself says so. This creates nothing and mails nothing.

Input parameters:

- `letter_id` (string, required)

Output parameters:

- `cancelled_at`
- `created_at` (string)
- `delivered_at`: Certified tiers only, and absent entirely for the tiers USPS does not scan.
- `delivery_confirmation` (boolean): False for every tier USPS does not scan at delivery. Never claim otherwise.
- `description` (string): One sentence for the user about where this letter is.
- `disclosure`: Say this to the user whenever an expected delivery date is shown.
- `expected_delivery_estimate`
- `letter_id` (string)
- `livemode` (boolean): False for sandbox letters, which are never mailed.
- `mail_date` (string): The calendar date (YYYY-MM-DD, New York time) this piece goes to USPS.
- `payment` (object)
- `scans` (array)
- `status` (string): Where the letter is. expected_delivery is the last state a standard or proof-of-mailing letter reaches; only certified tiers ever reach delivered.
- `tier` (string)
- `tracking_number` (string): USPS Certified Mail tracking number, present once the operator saves it.
- `tracking_url` (string): Direct USPS tracking link. Share it with the user when available.

### `list_letters` (~82 tokens)

List Letters

Return this account's letters, newest first, with the status, mail date and total for each. Use this to answer questions about what has already been sent. This creates nothing, changes nothing and mails nothing.

Input parameters:

- `limit` (integer): Defaults to 20.
- `starting_after` (string): The next_cursor from the previous call, to read the following page.

Output parameters:

- `has_more` (boolean)
- `letters` (array)
- `next_cursor`: Pass this back as starting_after for the next page.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/dev-paperagent-letters/paperagent#diagnostics

## Score history

- 2026-10-25: 83
- 2026-10-24: 82
- 2026-10-23: 82
- 2026-10-22: 81
- 2026-10-21: 81
- 2026-10-20: 81
- 2026-10-19: 80

## Common questions

### What is the PaperAgent — Send Physical Mail MCP server?

PaperAgent — Send Physical Mail is an MCP server listed in the public MCP registry as dev.paperagent/letters. Mail one-off USPS letters from ChatGPT or Claude after you approve the preview and price. US only. This page covers its hosted endpoint (https://paperagent.dev/mcp).

### Is the PaperAgent — Send Physical Mail MCP server safe to use?

PaperAgent — Send Physical Mail scores 83 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the PaperAgent — Send Physical Mail MCP server expose?

PaperAgent — Send Physical Mail exposes 8 tools: get_pricing, validate_address, create_draft, update_draft, preview_draft, and 3 more. Their descriptions and schemas cost roughly 1,483 tokens of context every time the server is loaded.

### Does the PaperAgent — Send Physical Mail MCP server require authentication?

Yes. PaperAgent — Send Physical Mail asked us for credentials when we connected, so you will need to authorise it in your MCP client before it can do anything.

### Is the PaperAgent — Send Physical Mail MCP server still maintained?

PaperAgent — Send Physical Mail is still listed as active in the MCP registry. We last reached this channel on 25 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://paperagent.dev/mcp
- Website: https://paperagent.dev/
- Changelog RSS feed: https://verifymcp.io/servers/dev-paperagent-letters/paperagent.xml
- Changelog JSON feed: https://verifymcp.io/servers/dev-paperagent-letters/paperagent.json
- HTML version of this page: https://verifymcp.io/servers/dev-paperagent-letters/paperagent