JsonMend
REMOTE · JSONMEND.MIKE-TUSA.WORKERS.DEV
Repair broken JSON from LLM output and validate it against a JSON Schema.
Available components
Last scanned (2 hours ago)
Scores higher than 57% of remote servers
Reachable. Last reached 17 Oct 2026.
Category Developer Tools
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 Security69
- 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 enforcement could not be verified: the plaintext port answered with HTTP 405, which proves neither a plaintext path nor enforcement. View diagnostics → Unverified
- 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 Usability63
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 975 tokens (~487/item across 2 items; 2 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 Management7
- Stability observed for 2 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 2 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 3 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.
- 17 Oct 26 +1
- Server version: 0.1.3 → 0.1.4 functional
- 16 Oct 26 0
- Stability: unverified → 0.03 ▲ functional
- 15 Oct 26 67
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://jsonmend.mike-tusa.workers.dev/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=mike-tusa.workers.dev | CN=WE1,O=Google Trust Services,C=US | 12 Oct 2026 | 10 Jan 2027 | ECDSA 256 | ECDSA-SHA256 | f05aa95d8943eeed0e4e86dd1f6f1e02 |
| SANs: mike-tusa.workers.dev, *.mike-tusa.workers.dev | ||||||
| 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 jsonmend.mike-tusa.workers.dev. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| dev. | present | 60074 | 8 | Verified |
| workers.dev. | 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 |
| x-content-type-options | nosniff |
| x-frame-options | DENY |
| referrer-policy | no-referrer |
| permissions-policy | interest-cohort=() |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://jsonmend.mike-tusa.workers.dev/mcp | Verified | 200 | |
| http (plaintext) | http://jsonmend.mike-tusa.workers.dev/mcp | Inconclusive | 405 |
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 →
repair_json Repair broken JSON (LLM output) and list the fixes ~386
Turn broken or messy JSON text into valid JSON. Strips Markdown code fences and prose before/after the JSON, removes comments and trailing commas, converts single/curly quotes, quotes unquoted keys, maps Python None/True/False, inserts missing commas, closes truncated strings/arrays/objects, and wraps NDJSON / several concatenated objects into one array. Returns the parsed value (json), the repaired text, and the list of fixes applied; valid input passes through unchanged with no fixes. Optional schema (+ coerce) also validates the result. Fails with isError (code unrepairable / no_json_found) when nothing JSON-like can be recovered. Pure computation: read-only, no network access, inputs not stored. Same engine and limits as POST /api/v1/repair.
| Name | Type | Req | Description |
|---|---|---|---|
| coerce | boolean | – | Convert values toward the schema's declared types before validating: "42" → 42, "true" → true, "null" → null, 5 → "5", x → [x]. Each change is listed in coercions. |
| draft | string | – | JSON Schema draft. Default: from the schema's $schema, else 2020-12. |
| format | string | – | Layout of the returned text: compact (default), pretty (2-space indent), or preserve (jsonrepair's output, keeps original spacing and long-number digits). |
| input | string | yes | The raw (possibly broken) JSON text, e.g. an LLM reply with code fences and prose around the JSON. Max 102,400 bytes (UTF-8). |
| schema | object | – | A JSON Schema (draft 2020-12 by default; 2019-09, 7 and 4 also supported). Only local $refs (#/...) resolve; remote $refs are an error. Max 32 KB. |
| Name | Type | Req | Description |
|---|---|---|---|
| changed | boolean | yes | false when the input was already valid JSON |
| fixes | array | yes | – |
| format | string | – | – |
| inputBytes | integer | – | – |
| inputWasValid | boolean | yes | – |
| json | – | yes | The repaired JSON value (coerced if coerce was used) |
| ok | boolean | yes | – |
| outputBytes | integer | – | – |
| plan | string | – | – |
| schema | object | – | – |
| values | integer | – | Number of top-level JSON values found (more than 1 = wrapped in an array) |
| version | string | – | – |
| warnings | array | – | – |
No examples provided.
validate_json Validate JSON against a JSON Schema (repairs broken input first) ~347
Check JSON against a JSON Schema and get every error with its JSON Pointer path. Send the JSON either as text ("input"; broken text is repaired first, and the fixes are listed) or as an already-parsed value ("data"). Optional coerce converts "42" → 42, "true" → true, etc. toward the schema's types before validating and lists each change. A schema mismatch is a normal result (valid: false), not an error. Drafts 2020-12 (default), 2019-09, 7, 4; only local $refs. Pure computation: read-only, no network access, inputs not stored. Same engine and limits as POST /api/v1/validate.
| Name | Type | Req | Description |
|---|---|---|---|
| coerce | boolean | – | Convert values toward the schema's declared types before validating: "42" → 42, "true" → true, "null" → null, 5 → "5", x → [x]. Each change is listed in coercions. |
| data | – | – | An already-parsed JSON value to validate. Send this or "input", not both. |
| draft | string | – | JSON Schema draft. Default: from the schema's $schema, else 2020-12. |
| input | string | – | JSON text to validate (repaired first if broken). Send this or "data", not both. Max 102,400 bytes. |
| schema | object | yes | A JSON Schema (draft 2020-12 by default; 2019-09, 7 and 4 also supported). Only local $refs (#/...) resolve; remote $refs are an error. Max 32 KB. |
| Name | Type | Req | Description |
|---|---|---|---|
| coerced | boolean | – | – |
| coercions | array | – | – |
| draft | string | – | – |
| errorCount | integer | yes | Total errors (at most 50 are listed); a lower bound when errorsTruncated is true |
| errors | array | yes | – |
| errorsTruncated | boolean | yes | true when the validator produced more than 5,000 raw errors and only the first 5,000 were examined |
| fixes | array | – | – |
| json | – | yes | The validated value (after repair and coercion) |
| ok | boolean | yes | – |
| plan | string | – | – |
| repaired | boolean | – | true when "input" needed repair before validation |
| valid | boolean | yes | – |
| version | string | – | – |
| warnings | array | – | – |
No examples provided.
How do I install the JsonMend MCP server?
JsonMend is a hosted endpoint at https://jsonmend.mike-tusa.workers.dev/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 · jsonmend.mike-tusa.workers.dev
claude mcp add --transport http dev-workers-mike-tusa-jsonmend-jsonmend 'https://jsonmend.mike-tusa.workers.dev/mcp'
What is the JsonMend MCP server?
JsonMend is an MCP server listed in the public MCP registry as dev.workers.mike-tusa.jsonmend/jsonmend. Repair broken JSON from LLM output and validate it against a JSON Schema. This page covers its hosted endpoint (https://jsonmend.mike-tusa.workers.dev/mcp).
Is the JsonMend MCP server safe to use?
JsonMend scores 68 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 JsonMend MCP server expose?
JsonMend exposes 2 tools: repair_json, validate_json. Their descriptions and schemas cost roughly 733 tokens of context every time the server is loaded.
Does the JsonMend MCP server require authentication?
No. We connected to JsonMend without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the JsonMend MCP server still maintained?
JsonMend 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.