SlickText MCP by usefulapi
REMOTE · SLICKTEXT.USEFULAPI.IO
Read SlickText contacts, lists, campaigns, analytics and inbox; create and update contacts.
Available components
Last scanned (8 hours ago)
Scores higher than 47% of remote servers
Reachable. Last reached 17 Oct 2026.
Category CRM and Sales
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 Security78
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- 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. View diagnostics → Pass
- HTTPS enforcement could not be verified: the plaintext port redirected somewhere other than https, so enforcement is unproven. View diagnostics → Unverified
- 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
- The authorisation server offers only Dynamic Client Registration (RFC 7591), which MCP 2026-07-28 deprecated in favour of Client ID Metadata Documents. View diagnostics → Partial
Transport & Reachability0
- Transport check failed: declared streamable-http, but the endpoint redirected instead of responding directly. See how to fix → View diagnostics → Fail
Schema Quality & AI Usability80
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 3396 tokens (~141/item across 24 items; 24 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 Management23
- Stability observed for 7 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage93
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 80% 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 24 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 25 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
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.
- 17 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.
- 15 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.
- 14 Oct 26 +2
- The server rewrote its instructions, which are the text every model session reads security
- The server now declares the “prompts” capability functional
- First check of Schema quality: 100 functional
- New prompt “getting_started” functional
- Server version: 1.4.0 → 1.5.0 functional
- 13 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.
- 11 Oct 26 +1
- Stability: unverified → 0.03 ▲ functional
- 10 Oct 26 59
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 17 Oct 2026 · Probed https://slicktext.usefulapi.io/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=usefulapi.io | CN=WE1,O=Google Trust Services,C=US | 13 Sept 2026 | 12 Dec 2026 | ECDSA 256 | ECDSA-SHA256 | d9be3287b0fde9630e825ba1f79bff3f |
| SANs: usefulapi.io, *.usefulapi.io | ||||||
| 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 slicktext.usefulapi.io. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| io. | present | 57355 | 8 | Verified |
| usefulapi.io. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication Enforced and verified
The endpoint asked for a token and published valid RFC 9728 metadata describing how to get one.
| Result | Enforced and verified |
|---|---|
| Enforced | On tool calls |
| HTTP status | 302 |
WWW-Authenticate challenge Bearer realm="OAuth", resource_metadata="https://slicktext.usefulapi.io/.well-known/oauth-protected-resource/mcp"
Bearer realm="OAuth", resource_metadata="https://slicktext.usefulapi.io/.well-known/oauth-protected-resource/mcp" Protected resource metadata
| Document | https://slicktext.usefulapi.io/.well-known/oauth-protected-resource/mcp |
|---|---|
| Retrieved | Yes |
| Resource | https://slicktext.usefulapi.io/mcp |
| Authorisation server | https://slicktext.usefulapi.io |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://slicktext.usefulapi.io/mcp | Redirected | 302 | https://usefulapi.io/slicktext/ |
| http (plaintext) | http://slicktext.usefulapi.io/mcp | Inconclusive | 302 | http://slicktext.usefulapi.io/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 →
slicktext_add_contact_to_lists Add a contact to lists ~134
WRITE: add one contact to one or more contact lists (it does not change the contact's opt-in status; lists are also campaign audiences). Returns SlickText's count of memberships added. WARNING: SlickText workflows can trigger on this event (Contact Created / Contact Field Changed / Contact Added to List) and may immediately SEND REAL TEXTS or take other actions configured in the brand's workflows. POST /brands/{brand_id}/lists/contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| contact_id | integer | yes | The contact id (a positive integer). |
| list_ids | array | yes | Contact list ids (from slicktext_list_lists). |
No output schema declared.
No examples provided.
slicktext_create_contact Create a contact ~368
WRITE: add a contact to the brand. By default the contact is created as 'not subscribed' and gets no text. Set opt_in_status='subscribed' ONLY for people who gave explicit permission to receive texts (SlickText has a zero-tolerance policy for unsolicited texts). force_double_opt_in=true makes SlickText SEND A REAL SMS to the number asking the person to confirm. Check slicktext_find_contact first to avoid duplicates. WARNING: SlickText workflows can trigger on this event (Contact Created / Contact Field Changed / Contact Added to List) and may immediately SEND REAL TEXTS or take other actions configured in the brand's workflows. POST /brands/{brand_id}/contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| address | string | – | – |
| birthdate | string | – | Birthday, YYYY-MM-DD. |
| city | string | – | – |
| country | string | – | – |
| custom_fields | object | – | Custom field values keyed by the field's internal_name (see slicktext_list_custom_fields), e.g. {"favorite_color": "blue"}. |
| string | – | – | |
| first_name | string | – | – |
| force_double_opt_in | boolean | – | true = SlickText texts the number a double opt-in confirmation (a real SMS). |
| language | string | – | Primary language code, e.g. "en". |
| last_name | string | – | – |
| mobile_number | string | yes | Mobile number (required), e.g. +16155553338 or (615) 555-3338. |
| opt_in_status | string | – | Default 'not subscribed'. 'subscribed' only with the person's explicit consent. |
| state | string | – | – |
| timezone | string | – | Contact time zone (SlickText accepts these four). |
| zip | string | – | – |
No output schema declared.
No examples provided.
slicktext_find_contact Find a contact by phone or email ~157
Find contacts by mobile number or email address (exact match). A 10-digit US number is matched as +1XXXXXXXXXX, the way SlickText stores numbers. Use it before creating a contact to avoid duplicates. GET /brands/{brand_id}/contacts?mobile_number=… or ?email=….
| Name | Type | Req | Description |
|---|---|---|---|
| string | – | Exact email address (case-sensitive, as stored). | |
| limit | integer | – | Results per page (1-100, default 25). |
| mobile_number | string | – | Mobile number, e.g. +16155553338 or (615) 555-3338. |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
No output schema declared.
No examples provided.
slicktext_get_analytics Get brand analytics ~312
Brand-level analytics. metric: contacts (current totals), contact_growth, contact_add_delete_events, opt_in_status_events, campaigns, messages (messages sent), message_credits, inbox_users (assignments, closures, response times per user), inbox_tags. Optional group (allowed per metric — contacts: source|opt_in_status; contact_growth/campaigns: contact_source; contact_add_delete_events: contact_source|type; opt_in_status_events: contact_source|contact_unsubscribe_source|opt_in_status; messages: source|status|direction|weekday; message_credits: source|status), a start/end range, frequency (hour/day/month/year) and compare (YoY, QoQ, MoM, WoW, DoD, PoP). GET /brands/{brand_id}/analytics/….
| Name | Type | Req | Description |
|---|---|---|---|
| compare | string | – | Compare with the previous period. |
| end | string | – | Range end, YYYY-MM-DD (= end of that day) or YYYY-MM-DD HH:MM[:SS] (SlickText's format, no time zone (passed through as is)). |
| frequency | string | – | Bucket size of the time series. |
| group | string | – | Group results by this field (allowed values depend on metric; see description). |
| metric | string | yes | Which analytics report. |
| start | string | – | Range start, YYYY-MM-DD or YYYY-MM-DD HH:MM[:SS] (SlickText's format, no time zone (passed through as is)). |
No output schema declared.
No examples provided.
slicktext_get_brand Get the brand ~61
Get the SlickText brand this API key belongs to: brand_id, name, website, sending-number registration details, opt-in / double-opt-in messages, inbox settings and the message credit limit. Every other tool works within this brand. GET /brands.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
slicktext_get_campaign Get a campaign ~57
Get one campaign by id: body, media_url, status, audience_size, schedule and completion. GET /brands/{brand_id}/campaigns/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| campaign_id | integer | yes | The campaign id (a positive integer). |
No output schema declared.
No examples provided.
slicktext_get_campaign_stats Get campaign performance ~96
Performance of one campaign: contacts reached, clicks, click_rate, unique clicks, unsubscribes, unsubscribe_rate, orders, revenue, average order value, revenue per message, plus the campaign, its audiences and links. GET /brands/{brand_id}/analytics/campaigns/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| campaign_id | integer | yes | The campaign id (a positive integer). |
| group | string | – | Group the results by source. |
No output schema declared.
No examples provided.
slicktext_get_contact Get a contact ~68
Get one contact by id: name, mobile_number, email, birthdate, address, opt_in_status, source, custom_fields, time zone and dates. GET /brands/{brand_id}/contacts/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| contact_id | integer | yes | The contact id (a positive integer). |
No output schema declared.
No examples provided.
slicktext_get_conversation Get an inbox conversation ~103
Get the content of one inbox conversation by its id (the _id from slicktext_list_conversations). For the message-by-message history also call slicktext_list_messages with source=InboxThread and source_id=<conversation id>. GET /brands/{brand_id}/inbox-threads/{id}/content.
| Name | Type | Req | Description |
|---|---|---|---|
| conversation_id | string | yes | The conversation _id, e.g. 6744a2ba587c8f2cf4028786. |
No output schema declared.
No examples provided.
slicktext_get_credit_usage Get message credit usage ~48
Message credits for the current billing period: total_credits (subscription + rollover + purchased), credits_used, credits_available and the credit limit. GET /brands/{brand_id}/usage.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
slicktext_get_keyword Get a keyword ~56
Get one keyword by id, including the contact_list_ids that people who text it are added to. GET /brands/{brand_id}/keywords/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| keyword_id | integer | yes | The keyword id (a positive integer). |
No output schema declared.
No examples provided.
slicktext_get_list Get a contact list ~70
Get one contact list by id plus its contact count (all statuses: subscribed, not subscribed, unsubscribed, blocked). GET /brands/{brand_id}/lists/{id} and /lists/{id}/contacts/count.
| Name | Type | Req | Description |
|---|---|---|---|
| list_id | integer | yes | The contact list id (a positive integer). |
No output schema declared.
No examples provided.
slicktext_list_campaigns List campaigns ~128
List the brand's SMS/MMS campaigns: name, body, status (e.g. draft, scheduled, queued, sent), scheduled/started/finished times, completion_percentage and audience (lists/segments and size). GET /brands/{brand_id}/campaigns.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
| status | string | – | Exact status, e.g. "sent", "scheduled", "draft". |
No output schema declared.
No examples provided.
slicktext_list_contacts List contacts ~198
List the brand's contacts (subscribers) with name, mobile_number, email, opt_in_status, source, custom_fields and dates. Filters are exact, case-sensitive matches (SlickText has no partial search). Paged: returns count, has_more and next_offset. GET /brands/{brand_id}/contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| custom_fields | object | – | Exact-match filters on custom fields, keyed by internal_name (see slicktext_list_custom_fields), e.g. {"favorite_color": "blue"}. |
| first_name | string | – | Exact first name (case-sensitive). |
| last_name | string | – | Exact last name (case-sensitive). |
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
| opt_in_status | string | – | Only contacts with this opt-in status. |
No output schema declared.
No examples provided.
slicktext_list_conversations List inbox conversations ~122
List two-way inbox conversations: status (open, pending, closed), the contact, the last message and its direction/time, assigned user, tags and unread state. GET /brands/{brand_id}/inbox-threads.
| Name | Type | Req | Description |
|---|---|---|---|
| assigned_to_user_id | integer | – | Only conversations assigned to this user id. |
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
| status | string | – | – |
No output schema declared.
No examples provided.
slicktext_list_custom_fields List custom fields ~90
List the brand's contact custom fields: name, internal_name (the key used in contact filters and writes), data_type and description. GET /brands/{brand_id}/custom-fields.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
No output schema declared.
No examples provided.
slicktext_list_inbox_tags List inbox tags ~85
List the inbox tags used to label conversations (inbox_tag_id, name, color, description). GET /brands/{brand_id}/inbox-tags.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
No output schema declared.
No examples provided.
slicktext_list_keywords List keywords ~105
List the brand's text-to-join keywords (word, description, active, auto-response and opt-in messages, double opt-in). GET /brands/{brand_id}/keywords.
| Name | Type | Req | Description |
|---|---|---|---|
| active | boolean | – | true = only active keywords, false = only inactive. |
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
No output schema declared.
No examples provided.
slicktext_list_list_contacts List contacts in a list ~108
List the contacts in one contact list (paged). GET /brands/{brand_id}/lists/{id}/contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| list_id | integer | yes | The contact list id (a positive integer). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
| opt_in_status | string | – | Only contacts with this opt-in status. |
No output schema declared.
No examples provided.
slicktext_list_lists List contact lists ~96
List the brand's contact lists (contact_list_id, name, description, created). Optional exact name filter. GET /brands/{brand_id}/lists.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| name | string | – | Exact list name (case-sensitive). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
No output schema declared.
No examples provided.
slicktext_list_messages List messages ~256
List individual SMS/MMS messages sent and received by the brand: to, from, body, direction, source (Campaign, Keyword, InboxThread, API …), status (delivered, undelivered …), credits and the contact. Filters are exact matches; use to/from with a phone number to read one contact's history, or source=InboxThread with source_id = a conversation id. GET /brands/{brand_id}/messages.
| Name | Type | Req | Description |
|---|---|---|---|
| direction | string | – | – |
| from | string | – | Sender number (incoming messages: the contact; outgoing: your number). |
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
| source | string | – | Exact source, e.g. "Campaign", "Keyword", "InboxThread", "API". |
| source_id | string | – | Id of the source (a campaign id, a conversation id …). |
| status | string | – | Exact status, e.g. "delivered", "undelivered". |
| to | string | – | Recipient number (outgoing messages: the contact; incoming: your number). |
No output schema declared.
No examples provided.
slicktext_list_segment_contacts List contacts in a segment ~92
List the contacts that currently match one segment (paged). GET /brands/{brand_id}/segments/{id}/contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
| segment_id | integer | yes | The segment id (a positive integer). |
No output schema declared.
No examples provided.
slicktext_list_segments List segments ~79
List the brand's segments (rule-based contact groups: segment_id, name, description). GET /brands/{brand_id}/segments.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Results per page (1-100, default 25). |
| offset | integer | – | Number of results to skip (default 0). Use next_offset from the previous page. |
No output schema declared.
No examples provided.
slicktext_update_contact Update a contact ~298
WRITE: change fields of an existing contact (only the fields you pass are sent). opt_in_status can mark a contact unsubscribed or blocked; set it to 'subscribed' ONLY when the person explicitly agreed to receive texts. WARNING: SlickText workflows can trigger on this event (Contact Created / Contact Field Changed / Contact Added to List) and may immediately SEND REAL TEXTS or take other actions configured in the brand's workflows. PUT /brands/{brand_id}/contacts/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| address | string | – | – |
| birthdate | string | – | Birthday, YYYY-MM-DD. |
| city | string | – | – |
| contact_id | integer | yes | The contact id (a positive integer). |
| country | string | – | – |
| custom_fields | object | – | Custom field values keyed by the field's internal_name (see slicktext_list_custom_fields), e.g. {"favorite_color": "blue"}. |
| string | – | – | |
| first_name | string | – | – |
| language | string | – | Primary language code, e.g. "en". |
| last_name | string | – | – |
| mobile_number | string | – | New mobile number. |
| opt_in_status | string | – | New opt-in status. 'subscribed' only with the person's explicit consent. |
| state | string | – | – |
| timezone | string | – | Contact time zone (SlickText accepts these four). |
| zip | string | – | – |
No output schema declared.
No examples provided.
How do I install the SlickText MCP by usefulapi server?
SlickText MCP by usefulapi is a hosted endpoint at https://slicktext.usefulapi.io/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 · slicktext.usefulapi.io
claude mcp add --transport http io-usefulapi-slicktext 'https://slicktext.usefulapi.io/mcp'
What is the SlickText MCP by usefulapi server?
SlickText MCP by usefulapi is listed in the public MCP registry as io.usefulapi/slicktext. Read SlickText contacts, lists, campaigns, analytics and inbox; create and update contacts. This page covers its hosted endpoint (https://slicktext.usefulapi.io/mcp).
Is the SlickText MCP by usefulapi server safe to use?
SlickText MCP by usefulapi scores 65 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 SlickText MCP by usefulapi server expose?
SlickText MCP by usefulapi exposes 24 tools: slicktext_get_brand, slicktext_get_credit_usage, slicktext_list_contacts, slicktext_find_contact, slicktext_get_contact, and 19 more. Their descriptions and schemas cost roughly 3,187 tokens of context every time the server is loaded.
Does the SlickText MCP by usefulapi server require authentication?
Yes. SlickText MCP by usefulapi 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 SlickText MCP by usefulapi server still maintained?
SlickText MCP by usefulapi is still listed as active in the MCP registry. We last reached this channel on 17 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.