# dVeracity > dVeracity is an emissions-verification platform: it validates sustainability > data against open standards including Open Footprint, checks EU CBAM records > and declarations against approved regulatory policies, issues > cryptographically attributable attestations, and exposes a verified > oil-and-gas emissions knowledge graph (PPDM, OGMP 2.0 methane) that AI agents > can query through a metered MCP server and REST API. API version: 0.8.2 ## MCP endpoint - Streamable HTTP: https://api.dveracity.com/mcp - Server card: https://api.dveracity.com/.well-known/mcp/server-card.json - OAuth protected-resource metadata: https://api.dveracity.com/.well-known/oauth-protected-resource/mcp - Authorization-server metadata: https://api.dveracity.com/.well-known/oauth-authorization-server ## Anonymous access - `initialize` and `tools/list` need no credential. - `billing_plans` is anonymous. It returns the current credit unit, the free-tier allowance and the offer catalogue, so an agent can answer "what does this cost?" without authorizing first. - Every other `tools/call` needs an identified caller. Free `ofp_*` reads are free of charge but still require identity. ## Authentication - OAuth 2.1 with PKCE. On a 401, follow the `WWW-Authenticate` challenge and use the authorization server advertised above. A free Explorer account is available through OAuth with a verified email. - API key: send `X-Api-Key: ` instead of a bearer token. - A bearer token that is presented but invalid is refused with `401 invalid_token` (RFC 6750), including on the anonymous `billing_plans` call. Refresh or drop the token; do not retry it as though the call were anonymous. - Client ID Metadata Documents are used only when the authorization-server metadata advertises `client_id_metadata_document_supported: true`. Do not assume CIMD support otherwise. Dynamic client registration is advertised separately in the same metadata. ## Pricing metadata - Every tool definition carries `_meta.pricing`: `{ "unit": "credit", "amount": , "usd": , "plan_required": ""? }`. - `plan_required` names the plan a tool needs; the plan-gated compliance tools carry `plan_required: "vaas"`. A zero `amount` means included in the plan, not free for every caller. - Prices and allowances are deployment configuration. Read the live values from `billing_plans` or the server card; they are deliberately not repeated in this file. ## Idempotency - Metered tools advertise `_meta.idempotency` with the accepted header, parameter and maximum key length. - Supply the key as the HTTP `Idempotency-Key` header on the `/mcp` request, or as `params._meta.idempotencyKey` on `tools/call`. - If both placements are present they must be equal. A mismatch, or an invalid key, is refused before any tool runs. ## Refusals - `401 auth_required`: the call needs an identified caller. The body names the expected `header`, `signupUrl`, `createKey`, `checkoutUrl` and `offers[]`. Authorize, then retry. - `401 invalid_token`: a bearer token was presented but is not valid. Refresh it; this is not an anonymous call. - `402 insufficient_credits`: the account cannot pay for this call. The body carries `balance`, `needed`, `explorerAllowance`, `offers[]` and a `checkoutUrl`. Relay `checkoutUrl` to the human operator; do not retry. - Clients matched by the hosted commerce policy (for example ChatGPT/OpenAI) receive `plansUrl` instead of `offers[]`/`checkoutUrl`. Show the pricing page and let the operator choose there. ## Explorer allowance Explorer is free: OAuth sign-up with a verified email. The current monthly metered-call allowance, the per-call credit ceiling it covers, and what it excludes are in `billing_plans.free_tier` (`monthly_metered_calls`, `max_call_cost`, `note`). Certification is not covered by the allowance. ## Tools Every entry below is advertised by `tools/list` and by the server card. `_meta.pricing` is authoritative for cost; the descriptions here do not quote prices. - `semantic_query`: Ask a natural-language question over verified emissions data. Metered; idempotency supported. - `semantic_templates`: List the query templates the semantic layer supports. - `credits_balance`: Read the caller's credit balance and recent usage. - `list_standards`: List the validation standards the platform supports. - `validate_data`: Validate a data payload against a published standard. Metered; idempotency supported. - `keri_identity`: Read the caller's KERI/vLEI identity information. - `ofp_models`: List the Open Footprint data models and their versions. - `ofp_search_entities`: Search Open Footprint entities by name or identifier. - `ofp_entity`: Read one Open Footprint entity and its attributes. - `ofp_sectors`: List Open Footprint sectors. - `ofp_sector`: Read one Open Footprint sector and its relevant terms. - `ofp_policies`: List sector policies and guardrails. - `compliance_policies`: List approved regulatory compliance policies. Plan-gated. - `compliance_policy`: Read one compliance policy. Plan-gated. - `compliance_evaluate`: Evaluate a payload against approved compliance policies. Plan-gated; metered; idempotency supported. - `compliance_evaluation`: Read a previous compliance evaluation. Plan-gated. - `compliance_policy_register`: Register a compliance policy. Plan-gated. - `ofp_validate`: Validate a payload against the Open Footprint model and sector guardrails. Metered; idempotency supported. - `ofp_semantics`: Look up O-DEF semantic terms. - `ofp_semantic_code`: Resolve an O-DEF semantic code. - `ofp_model_provenance`: Read provenance for an Open Footprint model. - `billing_plans`: Anonymous: the credit unit, free-tier allowance and current offer catalogue. - `billing_status`: Read the caller's plan, balance and subscription status. - `billing_purchase`: Start a credit-pack checkout for the signed-in caller. Returns `checkoutUrl`; adds `paymentLink` only when the deployment configures one. - `billing_subscribe`: Start a plan subscription checkout for the signed-in caller. ## Links - EU CBAM checks: https://dveracity.com/cbam (requires the VaaS plan; request access at https://dveracity.com/request-access?interest=vaas) - [Pricing](https://dveracity.com/pricing) - [Billing plans (JSON)](https://api.dveracity.com/api/v1/billing/plans) - [Semantic API manifest](https://dveracity.com/api/v1/semantic/manifest) - [Claude connector guide](https://dveracity.com/docs/claude) - [Server card](https://api.dveracity.com/.well-known/mcp/server-card.json) - [OAuth protected-resource metadata](https://api.dveracity.com/.well-known/oauth-protected-resource/mcp) - [Authorization-server metadata](https://api.dveracity.com/.well-known/oauth-authorization-server)