io.github.spruikco/send16-mcp
REMOTE · MCP.SEND16.COM · 2 COMPONENTS · SCANNED SEP 21
Email for AI agents: send mail, manage contacts, automations & webhooks. Zero-DNS first send.
Available components
Recent critical change
TLS certificate (24 Aug 2026). See the changelog before you install this server.
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. How we score → Why this is hard to score →
Endpoint Security77
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation is enforced on tool calls, but the challenge carries no valid RFC 9728 metadata, so a client cannot discover where to get a token. See how to fix → View diagnostics → Fail
- HTTPS enforcement could not be verified: the plaintext port answered with HTTP 404, which proves neither a plaintext path nor enforcement. View diagnostics → Unverified
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability82
- AI-judged instruction clarity (excellent).Pass
- Tool/resource definitions use about 6917 tokens (~87/item across 79 items; 79 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
- No destabilizing schema changes in the last 30 days.Pass
Tool Coverage96
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 87% of tool parameters carry a description.Partial
Tool Safety75
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- 0 of 14 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "send_email" implies "send" and declares no destructiveHint at all, which the MCP spec reads as destructive by default. See how to fix → Fail
- An AI judge read all 79 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
How do I install the io.github.spruikco/send16-mcp server?
io.github.spruikco/send16-mcp is a hosted endpoint at https://mcp.send16.com/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.
remote · mcp.send16.com
claude mcp add --transport http spruikco-send16-mcp 'https://mcp.send16.com/mcp'
{
"mcpServers": {
"spruikco-send16-mcp": {
"url": "https://mcp.send16.com/mcp"
}
}
} {
"servers": {
"spruikco-send16-mcp": {
"type": "http",
"url": "https://mcp.send16.com/mcp"
}
}
} [mcp_servers.spruikco-send16-mcp] url = "https://mcp.send16.com/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"spruikco-send16-mcp": {
"type": "remote",
"url": "https://mcp.send16.com/mcp",
"enabled": true
}
}
} openclaw mcp add spruikco-send16-mcp --url 'https://mcp.send16.com/mcp' --transport streamable-http
mcp_servers:
spruikco-send16-mcp:
url: "https://mcp.send16.com/mcp" {
"McpServers": {
"spruikco-send16-mcp": {
"Transport": "http",
"Url": "https://mcp.send16.com/mcp"
}
}
} assistant mcp add spruikco-send16-mcp -t streamable-http -u 'https://mcp.send16.com/mcp'
{
"mcpServers": {
"spruikco-send16-mcp": {
"type": "http",
"url": "https://mcp.send16.com/mcp"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 27 Aug 26 +17
- Authorization: unverified → fail ▼ security
- Injection markers: unverified → pass ▲ security
- Stability: unverified → pass ▲ security
- HSTS header: unverified → pass ▲ security
- TLS certificate: fail → pass ▲ security
- Transport: fail → pass ▲ security
- First check of Judged manipulation: pass security
- Endpoint reachability: unreachable → reachable ▲ functional
- Tool coverage: unverified → 100 ▲ functional
- MCP protocol: unverified → pass ▲ functional
- Score status: failed → scored ▲ functional
- First check of Destructive annotations: 0 functional
- 26 Aug 26 −17
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 24 Aug 26 0
- TLS certificate: pass → fail ▼ critical
- Score status: scored → failed ▼ critical
- Endpoint reachability: reachable → unreachable ▼ security
- Stability: 0.93 → unverified ▼ security
- Authorization: fail → unverified ▼ security
- HSTS header: pass → unverified ▼ security
- Transport: pass → fail ▼ security
- Capabilities: pass → unverified ▼ functional
- Tool coverage: 100 → unverified ▼ functional
- First check of Schema quality: unverified functional
- 11 Aug 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 2 Aug 26 0
- Tool “duplicate_campaign” rewrote its description, which is the text the model reads security
- Tool “create_contact” rewrote its description, which is the text the model reads security
- Tool “create_campaign” rewrote its description, which is the text the model reads security
- Tool “update_convo” rewrote its description, which is the text the model reads security
- Tool “update_campaign” rewrote its description, which is the text the model reads security
- Tool “list_campaigns” rewrote its description, which is the text the model reads security
- Tool “import_contacts” rewrote its description, which is the text the model reads security
- Schema quality: 79 → 87 ▼ functional
- Schema quality: good → excellent functional
- Server version: 0.5.8 → 0.5.13 functional
- “duplicate_campaign” added an optional parameter “segmentId” cosmetic
- “duplicate_campaign” added an optional parameter “name” cosmetic
- “duplicate_campaign” added an optional parameter “contactIds” cosmetic
- “duplicate_campaign” added an optional parameter “audienceIds” cosmetic
- “create_contact” added an optional parameter “audienceIds” cosmetic
- “create_campaign” added an optional parameter “tagIds” cosmetic
- “create_campaign” added an optional parameter “sendToAll” cosmetic
- “create_campaign” added an optional parameter “segmentId” cosmetic
- “create_campaign” added an optional parameter “html” cosmetic
- “create_campaign” added an optional parameter “contactIds” cosmetic
- “create_campaign” added an optional parameter “audienceIds” cosmetic
- “update_campaign” added an optional parameter “tagIds” cosmetic
- “update_campaign” added an optional parameter “sendToAll” cosmetic
- “update_campaign” added an optional parameter “segmentId” cosmetic
- “update_campaign” added an optional parameter “name” cosmetic
- “update_campaign” added an optional parameter “contactIds” cosmetic
- “update_campaign” added an optional parameter “audienceIds” cosmetic
- “list_campaigns” added an optional parameter “search” cosmetic
- “list_automation_enrollments” added an optional parameter “pageSize” cosmetic
- “list_automation_enrollments” added an optional parameter “page” cosmetic
- “import_contacts” added an optional parameter “audienceIds” cosmetic
- “duplicate_campaign” added an optional parameter “tagIds” cosmetic
- “duplicate_campaign” added an optional parameter “sendToAll” cosmetic
- “list_convos” reworded the description of “state” cosmetic
- “update_convo” reworded the description of “state” cosmetic
- “duplicate_campaign” reworded the description of “campaignId” cosmetic
- “create_contact” reworded the description of “tags” cosmetic
- “update_convo” reworded the description of “assigneeId” cosmetic
- “update_brand” reworded the description of “fontFamily” cosmetic
- “list_convos” reworded the description of “label” cosmetic
- “import_contacts” reworded the description of “tags” cosmetic
- “import_contacts” reworded the description of “csvData” cosmetic
- “update_campaign” dropped the optional parameter “templateSlug” cosmetic
- “update_convo” dropped the optional parameter “starred” cosmetic
- “list_convos” dropped the optional parameter “screener_status” cosmetic
- “list_convos” dropped the optional parameter “offset” cosmetic
- “list_automation_enrollments” dropped the optional parameter “limit” cosmetic
- “list_automation_enrollments” dropped the optional parameter “cursor” cosmetic
- 31 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 30 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 27 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 21 Sept 2026 · Probed https://mcp.send16.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=*.send16.com | CN=YE2,O=Let's Encrypt,C=US | 26 Aug 2026 | 24 Nov 2026 | ECDSA 256 | ECDSA-SHA384 | 65dc049671a0059a63297da3863d98d3273 |
| SANs: *.send16.com | ||||||
| CN=YE2,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 4df3b15dd6c0784c507cd37b58e6f115 |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of mcp.send16.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| send16.com. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication Challenged, unverified
The endpoint asked for a token, but we could not retrieve and validate the RFC 9728 metadata that tells a client how to obtain one.
| Result | Challenged, unverified |
|---|---|
| Enforced | On tool calls |
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000; includeSubDomains; preload |
| x-content-type-options | nosniff |
| x-frame-options | DENY |
| referrer-policy | strict-origin-when-cross-origin |
Protected resource metadata
| Retrieved | No |
|---|---|
| Problem | no_resource_metadata |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://mcp.send16.com/mcp | Verified | 200 | |
| http (plaintext) | http://mcp.send16.com/mcp | Inconclusive | 404 |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
list_topics ~70
List subscription topics. Topics are granular categories contacts can subscribe to (e.g. 'product-updates', 'weekly-digest'). Campaigns and automations can be gated to subscribers of a specific topic.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
No output schema declared.
No examples provided.
list_webhooks ~56
List configured outgoing webhooks (your endpoints that Send16 POSTs delivery events to). Outgoing webhooks are a plan feature.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
No output schema declared.
No examples provided.
list_workspaces ~44
List workspaces the authenticated user has access to (owner or member).
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
No output schema declared.
No examples provided.
mark_convo_read ~51
Mark a conversation as read for the current viewer.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| convoId | string | yes | Conversation ID |
No output schema declared.
No examples provided.
pause_automation ~56
Pause an automation. Existing enrollments freeze in place; no new contacts enroll.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| automationId | string | yes | Automation ID |
No output schema declared.
No examples provided.
pause_campaign ~55
Pause a sending campaign. Already-sent messages are unaffected; remaining sends halt.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| campaignId | string | yes | Campaign ID |
No output schema declared.
No examples provided.
pre_send_review ~101
Run an AI pre-send review on an email's HTML before sending. Surfaces tone issues, broken links, missing alt text, spam triggers, and accessibility problems.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| audience | string | – | Short description of the audience (helps tone analysis) |
| html | string | yes | Full HTML body to review |
| subject | string | yes | Email subject line |
No output schema declared.
No examples provided.
preview_campaign_recipients ~58
Preview the recipient set for a campaign before sending. Returns count + sample list.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| campaignId | string | yes | Campaign ID |
No output schema declared.
No examples provided.
preview_segment ~49
Preview the contacts that match a segment without sending.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| segmentId | string | yes | Segment ID |
No output schema declared.
No examples provided.
regenerate_webhook_secret ~60
Rotate the HMAC signing secret for an outgoing webhook endpoint. Returns the new secret once.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| webhookId | string | yes | Webhook ID |
No output schema declared.
No examples provided.
remove_contact_from_audience ~59
Remove a contact from an audience.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| audienceId | string | yes | Audience ID |
| contactId | string | yes | Contact ID |
No output schema declared.
No examples provided.
remove_suppression ~59
Remove an email from the suppression list. Use only when you've confirmed the recipient wants to receive mail again.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| string | yes | – |
No output schema declared.
No examples provided.
render_email_content ~108
Compile an EmailContent JSON object (the shape used by the Send16 builder + templates) into HTML using the platform's authoritative renderer. Returns the exact HTML the API would send. Useful for previews and post-processing.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| content | object | yes | EmailContent JSON (from get_template or the builder) |
| variables | object | – | Variable replacements (e.g. {firstName:'Alice'}) |
No output schema declared.
No examples provided.
resume_campaign ~44
Resume a paused campaign.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| campaignId | string | yes | Campaign ID |
No output schema declared.
No examples provided.
schedule_campaign ~99
Schedule (or send immediately) an existing draft campaign to an audience/segment/topic.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| audienceId | string | – | – |
| campaignId | string | yes | Campaign ID |
| scheduleAt | string | – | ISO-8601 future datetime; omit to send immediately |
| segmentId | string | – | – |
| topicId | string | – | – |
No output schema declared.
No examples provided.
screener_decide ~83
Decide a pending screener conversation (first-time sender). 'allow' lets future emails through, 'reject' blocks, 'cold' marks as cold outreach.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| convoId | string | yes | Conversation ID |
| decision | string | yes | Screener decision |
No output schema declared.
No examples provided.
search_contacts ~90
Search contacts by email address or name. Returns matching contacts with their tags and subscription status.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| page | integer | – | Page number |
| pageSize | integer | – | Results per page (max 100) |
| query | string | yes | Search query (matches against email, first name, last name) |
No output schema declared.
No examples provided.
send_broadcast ~220
One-shot broadcast: create a campaign and immediately schedule it to send, in a single call. Pass either an audienceId, segmentId, topicId, or fully-qualified filter. Provide html OR templateSlug.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| audienceId | string | – | Send to all contacts in this audience |
| fromEmail | string | yes | Must be a verified domain |
| fromName | string | yes | – |
| html | string | – | Full HTML body (one of html/templateSlug required) |
| name | string | yes | Internal campaign name |
| previewText | string | – | – |
| replyTo | string | – | – |
| scheduleAt | string | – | ISO-8601 future datetime; omit to send immediately |
| segmentId | string | – | Send to all contacts matching this segment |
| subject | string | yes | – |
| templateSlug | string | – | Workspace template slug to use |
| topicId | string | – | Send to all subscribers of this topic |
No output schema declared.
No examples provided.
send_campaign_test ~79
Send a test email for an existing campaign to preview how it will look in recipients' inboxes.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| campaignId | string | yes | Campaign ID to send test for |
| testEmail | string | yes | Email address to send the test to |
No output schema declared.
No examples provided.
send_email ~275
Send a transactional email through Send16. Provide `html`, `text`, or both (text-only is fine for OTPs/receipts/alerts). `from_email` must belong to a domain that is verified in the workspace — call `whoami` for the account and `list_domains` to see which senders are allowed; a send from an unverified domain returns a clear error, not a silent failure. For a zero-setup first send, use from_email `onboarding@send16.com` — the sandbox sender delivers with no DNS, but only to your own account email.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| from_email | string | – | Sender email address (must be from a verified domain) |
| from_name | string | – | Sender display name (e.g. "Acme Co") |
| html | string | – | HTML body content |
| reply_to | string | – | Reply-to email address |
| subject | string | yes | Email subject line |
| template | string | – | Transactional template slug to use instead of inline content |
| text | string | – | Plain text body content |
| to | – | yes | Recipient email address or array of addresses (max 50) |
| variables | object | – | Template variables for merge tags |
No output schema declared.
No examples provided.
send_event ~163
Fire a custom event for a contact. Automations whose trigger is `{type:'custom_event', eventName:'<name>'}` will enroll the contact and start running. Payload is exposed to condition steps as `event.<key>`.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| contactEmail | string | – | Contact email (provide either this or contactId) |
| contactId | string | – | Contact UUID (provide either this or contactEmail) |
| name | string | yes | Event name (e.g. 'trial_started', 'order.placed') |
| occurredAt | string | – | ISO-8601 timestamp; defaults to now |
| payload | object | – | Arbitrary JSON metadata available to automation conditions |
No output schema declared.
No examples provided.
send_reply ~94
Reply to an inbox conversation. The reply is sent from the original recipient address (the alias the convo arrived on) and threaded back to the contact.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| convoId | string | yes | Conversation ID |
| html | string | – | HTML body of the reply |
| text | string | – | Plain text body of the reply |
No output schema declared.
No examples provided.
update_action ~99
Update an Action (toggle enabled, change template, change event name).
| Name | Type | Req | Description |
|---|---|---|---|
| actionId | string | yes | Action ID |
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| delaySeconds | integer | – | – |
| enabled | boolean | – | – |
| eventName | string | – | – |
| name | string | – | – |
| sendOnce | boolean | – | – |
| templateSlug | string | – | – |
No output schema declared.
No examples provided.
update_brand ~131
Update workspace brand settings. The designSpec field is a Markdown DESIGN.md document fed into AI generation system prompts — use it to encode voice, do/don't lists, and visual rules.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| designSpec | string | – | Markdown DESIGN.md spec for AI generation |
| fontFamily | string | – | Body font family |
| logoUrl | string | – | – |
| primaryColor | string | – | Hex color (e.g. '#4F46E5') |
| secondaryColor | string | – | Hex color |
No output schema declared.
No examples provided.
update_campaign ~250
Update a draft campaign: name, subject, preview text, sender info, HTML content, and/or recipients. Retarget with exactly ONE of audienceIds / segmentId / contactIds / tagIds / sendToAll, then verify with preview_campaign_recipients before sending. Only drafts can be edited.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| audienceIds | array | – | Retarget to these audience IDs (see list_audiences). Sets recipient type 'lists'. |
| campaignId | string | yes | Campaign ID |
| contactIds | array | – | Retarget to these specific contact IDs |
| fromEmail | string | – | – |
| fromName | string | – | – |
| html | string | – | – |
| name | string | – | Campaign name (internal label) |
| previewText | string | – | – |
| replyTo | string | – | – |
| segmentId | string | – | Retarget to this segment (see list_segments) |
| sendToAll | boolean | – | Retarget to all subscribed contacts in the workspace |
| subject | string | – | – |
| tagIds | array | – | Retarget to contacts with these tag IDs |
No output schema declared.
No examples provided.
update_contact ~84
Update a contact's profile fields, custom fields, or subscription state.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| contactId | string | yes | Contact ID |
| customFields | object | – | – |
| firstName | string | – | – |
| lastName | string | – | – |
| subscribed | boolean | – | – |
No output schema declared.
No examples provided.
update_convo ~85
Update conversation status (open/closed/archived/snoozed) or assignee.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| assigneeId | – | – | Workspace member user ID, or null to unassign |
| convoId | string | yes | Conversation ID |
| state | string | – | New status |
No output schema declared.
No examples provided.
update_topic ~72
Update a subscription topic (name, description, default).
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
| description | string | – | – |
| isDefault | boolean | – | – |
| name | string | – | – |
| topicId | string | yes | Topic ID |
No output schema declared.
No examples provided.
whoami ~78
Verify the API key and return the authenticated workspace: name, plan, email quota (used/limit), and owner. Call this first to confirm the key works before sending. Pair with list_domains to see which `from` addresses are allowed.
| Name | Type | Req | Description |
|---|---|---|---|
| apiKey | string | – | Send16 API key (overrides SEND16_API_KEY env var) |
No output schema declared.
No examples provided.
What is the io.github.spruikco/send16-mcp server?
io.github.spruikco/send16-mcp is listed in the public MCP registry as io.github.spruikco/send16-mcp. Email for AI agents: send mail, manage contacts, automations & webhooks. Zero-DNS first send. This page covers its hosted endpoint (https://mcp.send16.com/mcp).
Is the io.github.spruikco/send16-mcp server safe to use?
io.github.spruikco/send16-mcp scores 86 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 io.github.spruikco/send16-mcp server expose?
io.github.spruikco/send16-mcp exposes 79 tools: whoami, send_email, send_campaign_test, create_campaign, design_email_template, and 74 more. Their descriptions and schemas cost roughly 6,917 tokens of context every time the server is loaded.
Does the io.github.spruikco/send16-mcp server require authentication?
Yes. io.github.spruikco/send16-mcp 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 io.github.spruikco/send16-mcp server still maintained?
io.github.spruikco/send16-mcp is still listed as active in the MCP registry. We last reached this channel on 21 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.