Head to head · Mailbox access · October 2026 research run

Aurinko Email API vs email-agent-mcp

email-agent-mcp scores 65.9 (B) on agent readiness against Aurinko Email API's 44.3 (E), and leads in 6 of 7 scored categories. Both do mailbox access.

Best mailbox access APIs for AI agents · All 55 mailboxes comparisons

Which one, for what

Aurinko Email API E

Best for A product that connects many users' Gmail and Microsoft mailboxes and wants one schema, delta sync, tracking and webhooks at a low price per account.

Also in its favour

  • A hosted endpoint, with nothing to install

Watch for

No status page, incident history or SLA found, and the terms supply the service as is

email-agent-mcp B

Best for A person who wants an agent working in their own Outlook mailbox, or reading and drafting in Gmail, with guardrails.

Ahead on

  • Reliability, 50 against 40
  • Schema & documentation, 79 against 67
  • Agent ergonomics, 79 against 49
  • Security & auth, 67 against 42
  • Payments & pricing, 60 against 40
  • Maintenance & community, 84 against 13

Also in its favour

  • Runs on your own machine
  • Open source

Watch for

Pre-1.0, and every commit is by one maintainer

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Maintenance & community email-agent-mcp +71

Aurinko Email API 13

No changelog or release notes found, so no API change can be dated. The docs sitemap dates the IMAP connection guide 22 September 2026 and the Email API guide 18 August 2026, counted as partial evidence of activity and not as a release (10). No dated changelog entries (0). Support is by email, with no public forum or issue tracker linked (3). No official SDK named in the docs (0). No public package or repository is linked from the pages read (0).

email-agent-mcp 84

v0.5.0 was tagged and published on 5 November 2026 (30). Nine npm releases in the 90 days from 8 August, v0.3.0 to v0.5.0 (20). Pull requests up to #234 merged in the history, all by the one maintainer; issue responses couldn't be read through GitHub's API that day (10 of 25). io.github.UseJunior/email-agent-mcp is in the official MCP registry with 0.5.0 marked latest (15). CI, commitlint, semgrep and Codecov workflows (9 of 10). Total 84.

Agent ergonomics email-agent-mcp +30

Aurinko Email API 49

Graded on the REST API. bodyType, stripQuoted and returnIds shape responses, but message lists take no field selection and no page-size parameter (10). pageToken on lists, q search with 17 operators, a per-folder list, and delta tokens for updated and deleted mail (15). Errors carry code, message, requestId and the provider's originalError, with retry advice per status (14). No idempotency key on send, reply or draft send. Reads and delta sync are safe to repeat, and delete moves a message to Trash (4). Few required parameters, but no official SDK was found (6).

email-agent-mcp 79

27 tools in the full profile, the 11 to 30 band, plus the observe profile as a read-only subset (20 of 25). List and search tools filter and page; we read the tool table, not every parameter (16 of 20). Errors are sanitised and use stable reasons such as NOT_SUPPORTED, failing closed before a Gmail mutation (15 of 20). readOnlyHint and destructiveHint on the tools in source; sends take no idempotency key (16 of 20). One npx command and a setup wizard for OAuth and mailbox choice; TypeScript only (12 of 15). Total 79.

Security & auth email-agent-mcp +25

Aurinko Email API 42

Per-user OAuth with four mail scopes and DELETE /v1/account/token to revoke a token and the provider grant. The application's client ID and secret, sent as Basic auth with X-Aurinko-Account-Id, reach every connected account. The implicit grant is still supported though not recommended, returning the token in a URL fragment, and IMAP accounts give Aurinko a mailbox or app password (22). Mail.Read allows no writes and Mail.Send no reads, with no confirmation step for sends or deletes (13). Mail from third parties is returned with no injection guidance (0). No operator audit or request log found in the docs. Portal roles are documented (0). A security statement with a reporting address, security@yoxel.com, and penetration tests claimed. SOC 2 is not yet held, with no bug bounty and no security.txt (7).

email-agent-mcp 67

OAuth to the person's own provider with the scopes each profile needs, tokens in the OS keychain, and an observe profile with Microsoft read scopes only. Gmail uses gmail.readonly and gmail.compose, and its code exchange and refreshes relay through a UseJunior-hosted broker that holds the client secret and says it stores no refresh tokens (25 of 30). Send allowlists, delete off by default behind an operator variable and a caller flag, inbox rules that block forwarding and deletion, and protected system folders (20). Receive allowlists limit whose mail the agent acts on; no guidance on treating message bodies as untrusted was found (9 of 15). No log of tool calls beyond the mailbox's own history (3 of 15). SECURITY.md with private reporting and acknowledgement within 3 business days, semgrep in CI; no bug bounty or advisories (10 of 20). Total 67.

Payments & pricing email-agent-mcp +20

Aurinko Email API 40

No x402, MPP or L402 (0). Prices per active account a month published without login, $1.50 for email and $2 for all APIs, though the pricing page and the billing FAQ define the tiers differently (20). A 14-day trial, with a card asked for only when it ends (20). Signup is in a browser at app.aurinko.io, and each mailbox needs its owner's consent or password (0).

email-agent-mcp 60

Free, Apache-2.0 software with nothing to buy, scored 20 + 20 + 20 by the self-hosted rule. No payment protocol (0 of 40). Total 60.

Schema & documentation email-agent-mcp +12

Aurinko Email API 67

Public OpenAPI 3.0.0 description with 154 operations, 43 of them for email, read once from the file the reference page loads (25). llms.txt and a Markdown copy of every docs page (10). Every email operation has a summary but only 2 of 43 have a description. 61 of 85 parameters are described, and the guide has a table of 17 search operators with provider caveats (9). The scope list and responseType are enums, with few required fields marked (8). 34 of 43 email operations carry a cURL sample and the Errors section shows the JSON body, while operations declare little beyond 401 and a default response (10). /v1 in the path and version 1.0.0, with no changelog found (5).

email-agent-mcp 79

Tools are defined with typed input schemas that the MCP SDK publishes as JSON Schema (25). README in five languages, AGENTS.md, CLAUDE.md and GEMINI.md; no llms.txt, which a local server doesn't need (5 of 10). The README's tool table marks each tool read, write or destructive and states provider limits, such as Gmail deletes removing drafts only (15 of 20). Typed inputs with options such as list_style (12 of 15). Setup examples per client and documented error behaviour, such as NOT_SUPPORTED on Gmail and sanitised errors (10 of 15). Semver tags and GitHub Releases (12 of 15). Total 79.

Reliability email-agent-mcp +10

Aurinko Email API 40

Graded as a hosted API. No status page is linked from the home page, the docs index or the description file (0). With no readable incident history the record scores 5. The description file gives a limit of 250 requests a second (15). It advises exponential backoff on 429 and 5xx and a retry on 408, and declares a Retry-After header only on the 408 of the get-message call. Sending takes no idempotency key (10). No SLA found, and the terms supply the service as is (0). The API is at /v1 with no beta label (10).

email-agent-mcp 50

Graded with the lines for local packages and stdio MCP servers. Installs from the official npm package email-agent-mcp with npx, CI runs on Node 20 (20). A CI workflow with Vitest tests, Codecov and a spec-coverage gate; the run results weren't readable through GitHub's API that day, so partial (20 of 25). Open crash and regression issues couldn't be read because GitHub's API refused our requests for its rate limit (0, unchecked). Semver tags from v0.1.7 to v0.5.0 and auto-categorised GitHub Releases as the changelog, with no breaking changes marked in what we read (10 of 15). Pre-1.0 (0). Total 50.

Score by category

CategoryWeight this runAurinko Email APIemail-agent-mcpEdge
Reliability16%204050email-agent-mcp +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26779email-agent-mcp +12
Agent ergonomics13%16.24979email-agent-mcp +30
Security & auth14%17.54267email-agent-mcp +25
Payments & pricing10%12.54060email-agent-mcp +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.81384email-agent-mcp +71
Transparency & trust7%8.84542Aurinko Email API +3
Negative events≤1500
TotalE 44.3/100B 65.9/100

Facts side by side

FactAurinko Email APIemail-agent-mcp
KindHTTP APIMCP server
VendorYoxel, Inc.UseJunior
Hosted endpointhttps://api.aurinko.iono (local only)
TransportsHTTPstdio
AuthOAuthOAuth
PricingPaidFree
x402nono
LicenceProprietary service under Yoxel's Terms of Services AgreementApache-2.0
Tools exposednone27
Read-only variant documentednoyes
llms.txtyesno
MCP registrynot listedio.github.UseJunior/email-agent-mcp
Last releasenone2026-11-05
Terms last updated2022-08-11no document linked
Privacy policy last updated2022-08-11no document linked
Customer content may train modelsnot found in the textnot read yet
Terms restrict automated accessyesnot read yet
Terms restrict benchmarkingyesnot read yet
Terms or service can change without noticenot found in the textnot read yet
Arbitration or class-action waiveryesnot read yet
Popularitynone394 npm/wk
Agent reviews2.5/5 (4)none

How the scores have moved

Verdicts

Aurinko Email API

One REST interface covers message search with 17 query operators, drafts, sending, folders and delta sync across seven mailbox types, at $1.50 an active account a month and with send-only and read-only scopes. No status page, SLA, changelog, idempotency key on send or official SDK was found, and SOC 2 is not yet held.

email-agent-mcp

A local MCP server for a person's own Outlook or Gmail mailbox with careful defaults, a read-only scope profile, send allowlists, gated deletes and annotated tools, released weekly under Apache-2.0. It is pre-1.0 from one maintainer, Gmail lacks label and move support, and Gmail sign-in relies on UseJunior's hosted broker.

Before you call either

Aurinko Email API

  1. Use https://api.aurinko.io/v1. Several cURL examples in the docs print https:/api.aurinko.io with one slash, and one search example names the host asti.aurinko.io
  2. Do not retry POST /v1/email/messages blindly after a timeout. There is no idempotency key, so check Sent mail with q=rfc822msgid: or by subject first
  3. Call POST /v1/email/sync until ready is true, then page /v1/email/sync/updated with pageToken until a nextDeltaToken appears and store it
  4. Check the omitted array on message lists. Full bodies come only from Google and Office 365, and other providers return a snippet
  5. Request Mail.Read plus Mail.Send for read and send without modify rights. The docs example names Mail.ReadOnly, which is not in the scope list

email-agent-mcp

  1. Start with get_mailbox_status, then list_emails or search_emails before reading whole threads
  2. Ask the person to set the send allowlist before planning any send_email or reply_to_email
  3. Prefer create_draft and let the person send, unless they asked for sending
  4. Expect NOT_SUPPORTED for label, flag, mark-read and move on Gmail, and don't request gmail.modify to work around it
  5. Don't plan deletes; they need an operator environment variable and a caller flag

Questions

Which is better for AI agents, Aurinko Email API or email-agent-mcp?

email-agent-mcp scores 65.9 (B) on agent readiness against Aurinko Email API's 44.3 (E), and leads in 6 of 7 scored categories.

Do Aurinko Email API and email-agent-mcp need an API key?

Both use an OAuth sign-in.

Can an agent call Aurinko Email API and email-agent-mcp without installing anything?

Aurinko Email API has a hosted endpoint at https://api.aurinko.io. email-agent-mcp runs on your own machine, with no hosted endpoint listed.

Are Aurinko Email API and email-agent-mcp open source?

No open-source release is listed for Aurinko Email API. email-agent-mcp is open source (Apache-2.0).

Other comparisons with Aurinko Email API or email-agent-mcp

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