B grade
auth-required
30 score
78 ms
100.0% uptime over 5 measured probes
AS16509 AMAZON-02 - Amazon.com, Inc., US · US
https://api.letter.ai/v1/mcp
mcp first seen 2026-09-07 · last seen 2026-09-11 · json
Listed in
| source | name | description | external id |
|---|---|---|---|
| Official MCP Registry | Letter AI | Search and act on Letter AI sales enablement content, deals, and call recordings. | io.github.tractatus-ai/letter |
| agent-tools.cloud | Letter AI | Search and act on Letter AI sales enablement content, deals, and call recordings. | mcp:letter-ai-api-letter-ai |
| Agenstry | Letter AI | mcp:io.github.tractatus-ai/letter |
Same host
agents-txt × 1 ard × 1 llms-txt × 1 robots × 1 sigdir × 1
Badge
embed:
<a href="https://agentprobe.org/endpoint/49005"><img src="https://agentprobe.org/badge/49005.svg" alt="agentprobe"></a>
Probe history
| probed (UTC) | outcome | score | status | http | ms | version | capabilities | error |
|---|---|---|---|---|---|---|---|---|
| 2026-09-11 09:06 | auth-required | 30 | 401 | HTTP/1.1 | 78 | detailsmeta {"final_url":"https://api.letter.ai/v1/mcp","www_authenticate":"Bearer realm=\"letter-mcp\", error=\"invalid_token\", error_description=\"API key auth failed: Missing Authorization header\", scope=\"mcp:read mcp:tools mcp:resources\", authorization_uri=\"https://api.letter.ai/oauth/authorize\", resource_metadata=\"https://api.letter.ai/.well-known/oauth-protected-resource/mcp\"","oauth":{"prm_url":"https://api.letter.ai/.well-known/oauth-protected-resource/mcp","resource":"https://api.letter.ai/v1/mcp","authorization_servers":["https://api.letter.ai"],"scopes_supported":["mcp:read","mcp:tools","mcp:resources"]},"http_version":"HTTP/1.1","vantage":"us-east-1"} | HTTP 400 | |
| 2026-09-10 09:02 | auth-required | 30 | 401 | HTTP/1.1 | 94 | detailsmeta {"final_url":"https://api.letter.ai/v1/mcp","www_authenticate":"Bearer realm=\"letter-mcp\", error=\"invalid_token\", error_description=\"API key auth failed: Missing Authorization header\", scope=\"mcp:read mcp:tools mcp:resources\", authorization_uri=\"https://api.letter.ai/oauth/authorize\", resource_metadata=\"https://api.letter.ai/.well-known/oauth-protected-resource/mcp\"","oauth":{"prm_url":"https://api.letter.ai/.well-known/oauth-protected-resource/mcp","resource":"https://api.letter.ai/v1/mcp","authorization_servers":["https://api.letter.ai"],"scopes_supported":["mcp:read","mcp:tools","mcp:resources"]},"http_version":"HTTP/1.1","vantage":"us-east-1"} | HTTP 400 | |
| 2026-09-09 08:05 | auth-required | 30 | 401 | 693 | detailsmeta {"final_url":"https://api.letter.ai/v1/mcp","www_authenticate":"Bearer realm=\"letter-mcp\", error=\"invalid_token\", error_description=\"API key auth failed: Missing Authorization header\", scope=\"mcp:read mcp:tools mcp:resources\", authorization_uri=\"https://api.letter.ai/oauth/authorize\", resource_metadata=\"https://api.letter.ai/.well-known/oauth-protected-resource/mcp\"","oauth":{"prm_url":"https://api.letter.ai/.well-known/oauth-protected-resource/mcp","resource":"https://api.letter.ai/v1/mcp","authorization_servers":["https://api.letter.ai"],"scopes_supported":["mcp:read","mcp:tools","mcp:resources"]},"vantage":"us-east-1"} | HTTP 400 | ||
| 2026-09-08 07:49 | auth-required | 30 | 401 | 93 | detailsmeta {"final_url":"https://api.letter.ai/v1/mcp","www_authenticate":"Bearer realm=\"letter-mcp\", error=\"invalid_token\", error_description=\"API key auth failed: Missing Authorization header\", scope=\"mcp:read mcp:tools mcp:resources\", authorization_uri=\"https://api.letter.ai/oauth/authorize\", resource_metadata=\"https://api.letter.ai/.well-known/oauth-protected-resource/mcp\"","oauth":{"prm_url":"https://api.letter.ai/.well-known/oauth-protected-resource/mcp","resource":"https://api.letter.ai/v1/mcp","authorization_servers":["https://api.letter.ai"],"scopes_supported":["mcp:read","mcp:tools","mcp:resources"]},"vantage":"us-east-1"} | |||
| 2026-09-07 03:15 | auth-required | 30 | 401 | 55 | detailsmeta {"final_url":"https://api.letter.ai/v1/mcp","www_authenticate":"Bearer realm=\"letter-mcp\", error=\"invalid_token\", error_description=\"API key auth failed: Missing Authorization header\", scope=\"mcp:read mcp:tools mcp:resources\", authorization_uri=\"https://api.letter.ai/oauth/authorize\", resource_metadata=\"https://api.letter.ai/.well-known/oauth-protected-resource/mcp\"","oauth":{"prm_url":"https://api.letter.ai/.well-known/oauth-protected-resource/mcp","resource":"https://api.letter.ai/v1/mcp","authorization_servers":["https://api.letter.ai"],"scopes_supported":["mcp:read","mcp:tools","mcp:resources"]}} |