Book a Sponsor
REMOTE · BOOKASPONSOR.COM
Find brands that already sponsor newsletters like yours, with sponsorship rates.
Available components
Last scanned (1 hour ago)
Scores higher than 93% of remote servers
Reachable. Last reached 5 Nov 2026.
Category Marketing and SEO
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 Security74
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one. See how to fix → View diagnostics → Partial
- 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 Usability82
- AI-judged instruction clarity (excellent).Pass
- Tool/resource definitions use about 454 tokens (~113/item across 4 items; 4 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management97
- Stability observed for 29 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 4 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 5 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
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.
- 5 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.
- 2 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 31 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 77 to 80. That category is still filling its 30-day observation window: 23 days of observed history at the previous scan, 24 at this one. The score rises as the window fills, whether or not the server changes.
- 29 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 70 to 73. That category is still filling its 30-day observation window: 21 days of observed history at the previous scan, 22 at this one. The score rises as the window fills, whether or not the server changes.
- 27 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 63 to 67. That category is still filling its 30-day observation window: 19 days of observed history at the previous scan, 20 at this one. The score rises as the window fills, whether or not the server changes.
- 25 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 57 to 60. That category is still filling its 30-day observation window: 17 days of observed history at the previous scan, 18 at this one. The score rises as the window fills, whether or not the server changes.
- 23 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 50 to 53. That category is still filling its 30-day observation window: 15 days of observed history at the previous scan, 16 at this one. The score rises as the window fills, whether or not the server changes.
- 21 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 43 to 47. That category is still filling its 30-day observation window: 13 days of observed history at the previous scan, 14 at this one. The score rises as the window fills, whether or not the server changes.
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 5 Nov 2026 · Probed https://bookasponsor.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=bookasponsor.com | CN=YE1,O=Let's Encrypt,C=US | 5 Oct 2026 | 3 Jan 2027 | ECDSA 256 | ECDSA-SHA384 | 58d592b75d2e04783e82ca7b47b59ef7e62 |
| SANs: bookasponsor.com, sponsorradar.co, www.bookasponsor.com, www.sponsorradar.co | ||||||
| CN=YE1,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 5ddd70dd31f801c85c186a7a04b80afe |
| 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 bookasponsor.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| bookasponsor.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://bookasponsor.com/mcp | Verified | 200 | |
| http (plaintext) | http://bookasponsor.com/mcp | HTTPS enforced | 308 | https://bookasponsor.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 →
find_newsletter_sponsors Find sponsors for a newsletter ~111
Use this when someone who runs a newsletter asks which brands might sponsor it or how to find sponsors for it. Takes the newsletter's web address, finds similar newsletters, and returns the brands that sponsored them, with the newsletters and dates where each ad ran. Starts a scan of the public newsletter pages if none exists; a new scan takes about 15 to 60 seconds.
| Name | Type | Req | Description |
|---|---|---|---|
| newsletter_url | string | yes | The newsletter's web address, such as yourname.substack.com or yournewsletter.com |
| Name | Type | Req | Description |
|---|---|---|---|
| message | string | yes | – |
| newsletter | – | yes | – |
| results_url | string|null | yes | – |
| similar_newsletters | array | yes | – |
| sponsors | array | yes | – |
| sponsors_total | number | yes | – |
| status | string | yes | – |
No examples provided.
get_newsletter_sponsorship_rates Get newsletter sponsorship rates ~78
Use this when someone asks how much to charge for a newsletter sponsorship or what newsletters charge for an ad. Returns the median price newsletters list for the main sponsor slot of one issue, by list size, read from their own advertise pages.
| Name | Type | Req | Description |
|---|---|---|---|
| subscribers | integer | – | The newsletter's subscriber count, to pick its size band |
| Name | Type | Req | Description |
|---|---|---|---|
| bands | array | yes | – |
| newsletters_priced | number | yes | – |
| read_on | string | yes | – |
| source_url | string | yes | – |
| your_band | string|null | yes | – |
No examples provided.
get_sponsor_scan Get a newsletter sponsor scan ~67
Use this to read the result of a sponsor scan that find_newsletter_sponsors started, for example when it reported that the scan was still running. Takes the same newsletter web address.
| Name | Type | Req | Description |
|---|---|---|---|
| newsletter_url | string | yes | The newsletter's web address used for find_newsletter_sponsors |
| Name | Type | Req | Description |
|---|---|---|---|
| message | string | yes | – |
| newsletter | – | yes | – |
| results_url | string|null | yes | – |
| similar_newsletters | array | yes | – |
| sponsors | array | yes | – |
| sponsors_total | number | yes | – |
| status | string | yes | – |
No examples provided.
list_brands_sponsoring_newsletters List brands sponsoring newsletters ~115
Use this when someone asks which companies or brands sponsor newsletters, overall or in a topic such as AI, finance or marketing. Returns the brands seen in the most newsletters in the last 12 months, mostly read from published issues.
| Name | Type | Req | Description |
|---|---|---|---|
| niche | string | – | Newsletter topic: ai, business, finance, tech, marketing, health, culture, food, productivity, crypto, dev, design, science, education, sports, climate, media, local, legal, travel. Leave out for all… |
| Name | Type | Req | Description |
|---|---|---|---|
| brands | array | yes | – |
| brands_seen | number | yes | – |
| newsletters_read | number | yes | – |
| niche | string|null | yes | – |
| source_url | string | yes | – |
| updated | string | yes | – |
No examples provided.
How do I install the Book a Sponsor MCP server?
Book a Sponsor is a hosted endpoint at https://bookasponsor.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 · bookasponsor.com
claude mcp add --transport http com-bookasponsor-book-a-sponsor 'https://bookasponsor.com/mcp'
What is the Book a Sponsor MCP server?
Book a Sponsor is an MCP server listed in the public MCP registry as com.bookasponsor/book-a-sponsor. Find brands that already sponsor newsletters like yours, with sponsorship rates. This page covers its hosted endpoint (https://bookasponsor.com/mcp).
Is the Book a Sponsor MCP server safe to use?
Book a Sponsor 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 Book a Sponsor MCP server expose?
Book a Sponsor exposes 4 tools: find_newsletter_sponsors, get_sponsor_scan, list_brands_sponsoring_newsletters, get_newsletter_sponsorship_rates. Their descriptions and schemas cost roughly 371 tokens of context every time the server is loaded.
Does the Book a Sponsor MCP server require authentication?
No. We connected to Book a Sponsor without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Book a Sponsor MCP server still maintained?
Book a Sponsor is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.