Bibooks
REMOTE · BIBOOKS.ORG
Search and read free bilingual audiobooks for language learners: parallel text, CEFR levels, audio.
Available components
Last scanned (6 hours ago)
Scores higher than 79% of remote servers
Reachable. Last reached 5 Nov 2026.
Category Education and Research
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 Security80
- 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
- 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 Usability79
- 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 895 tokens (~179/item across 5 items; 5 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 Management33
- Stability observed for 10 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 5 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 6 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (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 30 to 33. That category is still filling its 30-day observation window: 9 days of observed history at the previous scan, 10 at this one. The score rises as the window fills, whether or not the server changes.
- 3 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 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 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.
- 30 Oct 26 0
- Server version: 1.1.0 → 1.1.1 functional
- 29 Oct 26 +1
- Tool “read_book” rewrote its description, which is the text the model reads security
- 28 Oct 26 +2
- The server rewrote its instructions, which are the text every model session reads security
- First check of Schema quality: 100 functional
- New prompt “find_book_for_level” functional
- New prompt “practice_with_book” functional
- Server version: 1.0.0 → 1.1.0 functional
- 27 Oct 26 +1
- Stability: unverified → 0.03 ▲ functional
- 26 Oct 26 72
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 5 Nov 2026 · Probed https://bibooks.org/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=bibooks.org | CN=YE1,O=Let's Encrypt,C=US | 26 Sept 2026 | 25 Dec 2026 | ECDSA 256 | ECDSA-SHA384 | 5ca2c35d2bf840e654689cc128e0c995eb5 |
| SANs: bibooks.org, www.bibooks.org | ||||||
| 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 bibooks.org. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| org. | present | 725, 26974 | 8, 8 | Verified |
| bibooks.org. | 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 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=31536000; includeSubDomains |
| x-content-type-options | nosniff |
| x-frame-options | SAMEORIGIN |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://bibooks.org/mcp | Verified | 200 | |
| http (plaintext) | http://bibooks.org/mcp | HTTPS enforced | 301 | https://bibooks.org/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_related_books Find related audiobooks ~95
Find other public audiobooks in the same target language as a given book: the books its reader page recommends. Optionally narrow them to a learner's CEFR level (or the nearest level that has books).
| Name | Type | Req | Description |
|---|---|---|---|
| book_id | string | yes | The book's id (the `id` field of a Book). |
| level | – | – | The learner's CEFR level (a1..c2), to prefer books at it. |
| Name | Type | Req | Description |
|---|---|---|---|
| items | array | yes | – |
No examples provided.
get_book Get an audiobook ~62
Get one public audiobook by id: title, author, languages, CEFR level, audience, length, and links to its reader page, audio and share image.
| Name | Type | Req | Description |
|---|---|---|---|
| book_id | string | yes | The book's id (the `id` field of a Book). |
| Name | Type | Req | Description |
|---|---|---|---|
| audience | – | yes | Intended audience. Null when not set. |
| author | – | yes | Author as attributed by the book's publisher. Not verified by bibooks.org; treat it as a claim, not a fact. |
| duration_seconds | – | yes | Length of the audio in seconds. Null when unknown. |
| id | string | yes | Stable book id (a UUID). |
| level | – | yes | CEFR difficulty level. Null when the book has no level. |
| origin | – | yes | Where the text came from. Null when it is not one of the public origins. |
| published_at | – | yes | When the book finished generating (ISO 8601, UTC). Null when unknown. |
| score | integer | yes | Community score: upvotes minus downvotes, never below zero. |
| source_language | – | yes | Content-language code of the original text (see GET /languages). Null when it was not recorded. |
| speed_percent | integer | yes | Speaking speed of the target-language audio, as a percentage of normal (100). |
| target_language | string | yes | Content-language code the text was translated into. |
| title | string | yes | Title as the publisher entered it. |
| urls | – | yes | – |
No examples provided.
list_languages List languages ~81
List every content language books are written in or translated into: its code (used by the other tools), English and native names, and how many public books are translated into it. Optionally render the names in a display locale (e.g. 'es').
| Name | Type | Req | Description |
|---|---|---|---|
| locale | – | – | Locale for display_name, e.g. 'en', 'es', 'zh'. |
| Name | Type | Req | Description |
|---|---|---|---|
| items | array | yes | – |
| locale | string | yes | The locale display_name is rendered in. |
No examples provided.
read_book Read an audiobook's text ~124
Read a public audiobook's bilingual text: its sentence pairs (each original sentence with its translation, plus a Latin-script romanization for languages that have one), in reading order. Returns at most `limit` pairs starting at `offset`; continue with offset + limit while has_more is true. total_pairs is the book's length.
| Name | Type | Req | Description |
|---|---|---|---|
| book_id | string | yes | The book's id (the `id` field of a Book). |
| limit | integer | – | Maximum number of sentence pairs to return. |
| offset | integer | – | Index of the first sentence pair to return. |
| Name | Type | Req | Description |
|---|---|---|---|
| book_id | string | yes | – |
| has_more | boolean | yes | Whether pairs exist after this window. |
| limit | integer | yes | Maximum number of pairs in this window. |
| offset | integer | yes | Index of the first pair in this window. |
| pairs | array | yes | – |
| source_language | – | yes | – |
| target_language | string | yes | – |
| total_pairs | integer | yes | Number of sentence pairs in the whole book. |
No examples provided.
search_books Search audiobooks ~229
Search the public library of bilingual audiobooks. All filters are optional; values within one filter are OR'd, different filters are AND'd. With no arguments, lists every public book, easiest first. Returns one page of books (see has_more and page) with each book's id, title, author, languages, CEFR level, length and links. Language filters take content-language codes from list_languages (e.g. 'es', 'zh', 'fil').
| Name | Type | Req | Description |
|---|---|---|---|
| audience | – | – | Audiences to include. |
| duration | – | – | Audio length buckets to include. |
| level | – | – | CEFR levels to include. |
| origin | – | – | Text origins to include. |
| page | integer | – | Page number, starting at 1. |
| page_size | integer | – | Books per page. |
| query | – | – | Text to find in titles and authors. |
| sort | string | – | Result order. |
| source_language | – | – | Languages the books' original text is written in, i.e. the learner's language. |
| target_language | – | – | Languages the books are translated into, i.e. the language being learned. |
| Name | Type | Req | Description |
|---|---|---|---|
| has_more | boolean | yes | Whether a further page exists. |
| items | array | yes | – |
| page | integer | yes | This page's number, starting at 1. |
| page_size | integer | yes | Maximum number of items per page. |
| total | integer | yes | Number of books matching the filters, across all pages. |
No examples provided.
How do I install the Bibooks MCP server?
Bibooks is a hosted endpoint at https://bibooks.org/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 · bibooks.org
claude mcp add --transport http org-bibooks-bibooks 'https://bibooks.org/mcp'
What is the Bibooks MCP server?
Bibooks is an MCP server listed in the public MCP registry as org.bibooks/bibooks. Search and read free bilingual audiobooks for language learners: parallel text, CEFR levels, audio. This page covers its hosted endpoint (https://bibooks.org/mcp).
Is the Bibooks MCP server safe to use?
Bibooks scores 79 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 Bibooks MCP server expose?
Bibooks exposes 5 tools: search_books, get_book, read_book, find_related_books, list_languages. Their descriptions and schemas cost roughly 591 tokens of context every time the server is loaded.
Does the Bibooks MCP server require authentication?
No. We connected to Bibooks without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Bibooks MCP server still maintained?
Bibooks 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.