Whenna
REMOTE · WHENNA.COM · SCANNED SEP 25
Group scheduling: create a plan link, mark availability, get best times, lock the final time.
Available components
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 Security57
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation not fully verified: no authorisation is required to call this server, and 7 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe. See how to fix → View diagnostics → Unverified
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- 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 Usability67
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 1384 tokens (~197/item across 7 items; 7 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- 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 Coverage90
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 70% of tool parameters carry a description.Partial
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 7 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 8 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 Whenna MCP server?
Whenna is a hosted endpoint at https://whenna.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 · whenna.com
claude mcp add --transport http com-whenna-whenna 'https://whenna.com/mcp'
{
"mcpServers": {
"com-whenna-whenna": {
"url": "https://whenna.com/mcp"
}
}
} {
"servers": {
"com-whenna-whenna": {
"type": "http",
"url": "https://whenna.com/mcp"
}
}
} [mcp_servers.com-whenna-whenna] url = "https://whenna.com/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"com-whenna-whenna": {
"type": "remote",
"url": "https://whenna.com/mcp",
"enabled": true
}
}
} openclaw mcp add com-whenna-whenna --url 'https://whenna.com/mcp' --transport streamable-http
mcp_servers:
com-whenna-whenna:
url: "https://whenna.com/mcp" {
"McpServers": {
"com-whenna-whenna": {
"Transport": "http",
"Url": "https://whenna.com/mcp"
}
}
} assistant mcp add com-whenna-whenna -t streamable-http -u 'https://whenna.com/mcp'
{
"mcpServers": {
"com-whenna-whenna": {
"type": "http",
"url": "https://whenna.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.
- 25 Sept 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
- 26 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
- 25 Aug 26 0
- Stability: 0.97 → pass security
- 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
- 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
- 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
- 26 Jul 26 0
First indexed and scored.
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 25 Sept 2026 · Probed https://whenna.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=whenna.com | CN=WE1,O=Google Trust Services,C=US | 31 Aug 2026 | 29 Nov 2026 | ECDSA 256 | ECDSA-SHA256 | d07efb2774d651dc1311bf02e3d9851a |
| SANs: whenna.com, *.whenna.com | ||||||
| CN=WE1,O=Google Trust Services,C=US (CA) | CN=GTS Root R4,O=Google Trust Services LLC,C=US | 13 Dec 2023 | 20 Feb 2029 | ECDSA 256 | ECDSA-SHA384 | 7ff31977972c224a76155d13b6d685e3 |
| CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) | CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE | 15 Nov 2023 | 28 Jan 2028 | ECDSA 384 | SHA256-RSA | 7fe530bf331343bedd821610493d8a1b |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of whenna.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| whenna.com. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://whenna.com/mcp | Verified | 200 | |
| http (plaintext) | http://whenna.com/mcp | HTTPS enforced | 301 | https://whenna.com/mcp |
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 →
whenna_best_times ~49
Ranked best meeting times for a plan: contiguous blocks where the most participants are free, with who is free in each block.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | – |
| top | integer | – | – |
No output schema declared.
No examples provided.
whenna_create_plan ~442
Create a Whenna plan (a shareable link that finds the time everyone is free). Returns the link to share with humans or other agents, and a creator_key that authorizes locking the final time. Times are wall-clock in the given IANA timezone. For a RECURRING plan ("every Tuesday"), pass weekday names in days (e.g. ["Tuesday"] or ["Tue","Thu"]) — the plan then has no dates and calendar events repeat weekly.
| Name | Type | Req | Description |
|---|---|---|---|
| days | array | yes | Candidate days: YYYY-MM-DD dates; OR weekday names (Mon…Sun) for weekly; OR ["daily"]; OR for monthly a single rule like ["15"] (day of month) or ["2nd Wednesday"] / ["last Friday"]. Do not mix forms. |
| end_hour | integer | yes | Latest hour to consider (1-24, exclusive) |
| every_weeks | integer | – | Repeat interval for recurring plans (with frequency: 2+weekly = every other week, 2+monthly = every other month, 3+daily = every 3 days) |
| frequency | string | – | How a recurring plan repeats. monthly requires days to be one rule: a day-of-month ("15") or an nth weekday ("2nd Wednesday", "last Friday"). Default weekly. |
| language | string | – | Optional 2-letter language for emails to notify_email (en es pt fr de it nl ru tr id hi ja ko zh ar). Default en. |
| location | string | – | Optional place ("Nonna's, 5th Ave") — shown on the plan and embedded in everyone's calendar event |
| notify_email | string | – | Optional creator email: gets an alert on the first answer, digests after, a "everyone's free" moment, and the lock confirmation. Every email has one-click unsubscribe. |
| slot_minutes | integer | – | Time-slot precision |
| start_hour | integer | yes | Earliest hour to consider (0-23) |
| timezone | string | – | IANA timezone, e.g. America/Chicago |
| title | string | yes | What the plan is, e.g. "Team dinner" |
No output schema declared.
No examples provided.
whenna_get_plan ~97
Fetch a Whenna plan: title, window, every participant's availability, ranked best times, the locked final time if set, and a negotiation brief — state (awaiting_answers | collecting | everyone_overlaps | locked), who has answered, and suggested_next_step telling an agent the best next move. Poll this between actions when coordinating.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | Plan id (the part after /o/ in the link) |
No output schema declared.
No examples provided.
whenna_lock_time ~167
Lock the final time on a plan (requires the creator_key returned by whenna_create_plan). Pass use_best:true to lock the top-ranked best time automatically, or give an explicit day/start. Everyone viewing the link sees it as confirmed, with add-to-calendar buttons. Returns calendar links (Google, Outlook, .ics).
| Name | Type | Req | Description |
|---|---|---|---|
| creator_key | string | yes | – |
| day | string | – | YYYY-MM-DD date, or a weekday name for weekly plans (matching the plan's days) |
| id | string | yes | – |
| minutes | integer | – | Duration in minutes |
| start | string | – | Start time HH:MM (24h, plan timezone) |
| use_best | boolean | – | Lock the current #1 best time (most participants free); day/start not needed. |
No output schema declared.
No examples provided.
whenna_mark_availability ~159
Set a participant's free times on a plan (replaces that participant's previous answer). Express availability as free ranges per day; the server converts them to slots. Use the participant's human name so the group recognizes them. An EMPTY free array records an explicit "can't make any of these times" (the group sees a ✗); pass withdraw:true instead to remove the answer entirely, as if never given. The result reports any ranges that could not be applied and why.
| Name | Type | Req | Description |
|---|---|---|---|
| free | array | – | Free ranges. Empty array = explicit "can't make any". |
| id | string | yes | – |
| name | string | yes | Participant display name |
| withdraw | boolean | – | Remove this participant's answer entirely (ignores free). |
No output schema declared.
No examples provided.
whenna_plan_next ~131
Group memory: start the group's next plan from a finished one. Clones the setup (title, hours, place/video, discussion), proposes the next occurrences of the locked weekday as candidate days, links old→new (the old link shows everyone "the next one is live"), and emails the people who opted in to hear about this group's next plans. Requires creator_key. Returns the new plan and its own creator_key — keep it to lock the new time. Idempotent: if a successor already exists it is returned.
| Name | Type | Req | Description |
|---|---|---|---|
| creator_key | string | yes | – |
| id | string | yes | – |
No output schema declared.
No examples provided.
whenna_set_place ~122
Set where the group meets: a place name, or video_call:true to attach Whenna's built-in encrypted video room (the room link then goes on everyone's calendar automatically). Place and video room are mutually exclusive. Requires creator_key.
| Name | Type | Req | Description |
|---|---|---|---|
| creator_key | string | yes | – |
| id | string | yes | – |
| location | string | – | Place name, e.g. "Nonna's, 5th Ave". Empty string clears it. |
| video_call | boolean | – | true = meet on Whenna's encrypted video room instead of a physical place |
No output schema declared.
No examples provided.
What is the Whenna MCP server?
Whenna is an MCP server listed in the public MCP registry as com.whenna/whenna. Group scheduling: create a plan link, mark availability, get best times, lock the final time. This page covers its hosted endpoint (https://whenna.com/mcp).
Is the Whenna MCP server safe to use?
Whenna scores 76 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 Whenna MCP server expose?
Whenna exposes 7 tools: whenna_create_plan, whenna_get_plan, whenna_mark_availability, whenna_set_place, whenna_plan_next, and 2 more. Their descriptions and schemas cost roughly 1,167 tokens of context every time the server is loaded.
Does the Whenna MCP server require authentication?
No. We connected to Whenna without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Whenna MCP server still maintained?
Whenna is still listed as active in the MCP registry. We last reached this channel on 25 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.