CarbonMeld API (v1)
REST API v1 with the 30-day Premium pass: project records, filtered lists and market stats. Bearer key, 300 requests per day per key.
What the API returns
Read the project data that CarbonMeld holds: project lists, market statistics and individual records with available quality scores and document-based analysis. A project record combines public data with Premium details when available. Scores and analysis depend on the published record; a pass does not create missing analysis.
Get your key
Sign in to the account box with an active 30-day Premium pass, then generate an API key. Copy it when shown: it is displayed only once. Regenerating revokes your previous key. The key stops authenticating when your pass expires and works again after a new purchase, unless revoked.
Open your account boxAuthentication
Send the key in the Authorization header on every request. Keys start with cmk_ followed by 64 lowercase hexadecimal characters. The examples use a placeholder: replace it locally with your own key and keep that key private.
Authorization: Bearer cmk_YOUR_KEY_HEREEndpoints
| Request | Response |
|---|---|
GET /api/v1/stats | Market statistics from the current export, including project and registry counts and updated_at. These are indexed projects, not a count of completed assessments. |
GET /api/v1/projects | Filtered project list: updated_at, total (after filtering), limit, offset and projects. |
GET /api/v1/projects/<id_or_slug> | One project by registry code, canonical slug or alias. Premium details, when available, share the daily project quota. |
Project list parameters
| Parameter | Accepted values |
|---|---|
registry | Standard code present in the data, case-insensitive (for example VCS). An unknown value returns 400 with the valid values. |
min_score | Number from 0 to 10. When provided, even 0 excludes projects without a numeric score. Omit to include unscored projects. |
limit | Decimal integer from 1 to 200; default 50. |
offset | Non-negative decimal integer; default 0. |
Limits and fair use
- 300 requests per day per key by default, shared by REST and MCP.
- 30 different Premium projects per day, shared across the website, PDF reports, REST and MCP. Reopening the same project that day counts once. Portfolio projects and projects unlocked for you are exempt; public-only records do not consume this project quota.
Daily counters reset at 00:00 UTC. A burst limit also applies: 120 requests per minute per IP. List and statistics requests count towards the request limit, not the Premium project quota.
Errors
| Status | Meaning and next step |
|---|---|
400 | Invalid project identifier or list parameter. Check the error message and accepted values. |
401 | Missing, invalid or revoked key, or no active pass. Check the Authorization header and your account. |
404 | Project not found. Check the registry code or slug. |
429 | Request, burst or project limit reached. Respect the Retry-After response header. |
503 | The project is being updated. Respect Retry-After and retry later. |
Example requests
Read a filtered list, then request one record by registry code. The second request can consume a Premium project view.
curl 'https://carbonmeld.com/api/v1/projects?registry=VCS&min_score=7&limit=5&offset=0' \
-H 'Authorization: Bearer cmk_YOUR_KEY_HERE'
curl 'https://carbonmeld.com/api/v1/projects/VCS-1318' \
-H 'Authorization: Bearer cmk_YOUR_KEY_HERE'What the API does not do
This is read access to CarbonMeld data. It does not integrate registry issuance or MRV workflows, issue or transfer credits, or validate ownership of individual serial numbers. Registry labels and recorded quantities describe the records we hold; they are not a guarantee about an offer.
Terms
Read the usage conditions and the explanation of the scoring methodology before using the data in your work.
Terms of UseUse it from an AI assistant
The MCP server uses the same API key and quotas.
MCP guide