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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

Ambr

Ricardian contracts for AI agents — dual-format, SHA-256 bound, legible by construction.

Checks passed
13 / 22

1 failed · 8 not measured

Median response
144 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
7

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
312

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 144 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name ambr-mcp-server.

  • Pass
    Lists tools

    tools/list returned 7 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 144 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 144 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    22 of 23 parameters have a description (96%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Pass
    Repo owner matches

    The GitHub repository owner matches the namespace login.

  • Fail
    Recently updated

    Updated 2026-04-21T14:34:15.300403Z, which is older than 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using Ambr

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http ambr https://getamber.dev/api/mcp

Capabilities

Tools 7

ambr_agent_handshake

Initiate a handshake on a contract on behalf of your delegating principal. Requires an API key with an active delegation (principal wallet registered via /api/v1/delegations). Records the agent's intent to accept, reject, or request changes on the contract. The principal must separately approve via wallet signature on the Reader Portal. Args: - contract_id (string, required): Contract ID (amb-YYYY-NNNN), SHA-256 hash, or UUID - intent (string, required): "accept" | "reject" | "request_changes" - message (string, optional): Note for the counterparty - visibility_preference (string, optional): "private" | "metadata_only" | "public" | "encrypted" Returns: Handshake status and next steps for principal approval. Legibility: the handshake itself is auditable — delegation scope, agent identity, and principal approval are recorded alongside the contract hash.

Discovered
ambr_check_transaction

Check one payment against what an agreement allows. Advisory only: Ambr compares what you report with the agreement's terms; it does not authorize, block or see payments, and in_scope is not an approval or a guarantee. Tests the payment against the agreement's status, validity window, currency, per-transaction limit, monthly limit, approved categories, enumerated actions and approval threshold. If the agreement was amended, the newest approved version is checked. Free: no credits are burned. Ambr does not hold funds or track spend, so the monthly limit is checked only when you pass period_spent. A rule the agreement sets no limit for comes back as not_evaluated, never as a pass. If a rule has a limit but you did not send what it needs (category, action, currency, period_spent), the verdict is "incomplete", not "in_scope". Send everything the agreement limits. Access: a public contract is open to anyone; otherwise use the creator's API key or pass a share_token. Args: - contract_id (string, required): Contract ID (amb-YYYY-NNNN), SHA-256 hash, or UUID - amount (number, required): payment amount, zero or more - currency (string, optional): e.g. "USD" - category (string, optional): spending category - action (string, optional): the action the agent is taking - period_spent (number, optional): already spent this month, to check the monthly limit - share_token (string, optional): share token for a private contract Returns: verdict ("in_scope" | "out_of_scope" | "incomplete" | "needs_approval"), the per-rule checks, plain-language reasons, and the contract that was checked (contract_id, effective_contract_id, sha256_hash, reader_url).

Discovered
ambr_create_contract

Generate a Ricardian Contract from a template. Creates a dual-format contract (human-readable legal text + machine-parsable JSON) using AI, linked by SHA-256 hash. The contract is stored on Ambr and accessible via the Reader Portal. Requires a valid API key (X-API-Key header on the HTTP request) with available credits. Use ambr_list_templates first to discover templates and their required parameters. Args: - template (string, required): Template slug (e.g. "d1-general-auth") - parameters (object, required): Template-specific parameters matching the schema - principal_declaration (object, required): { agent_id, principal_name, principal_type } - principal_wallet (string, optional): the deploying party's own wallet. It must differ from the counterparty wallet in parameters (same_wallet_both_parties otherwise); left out, the first wallet that signs fills the principal side - parent_contract_hash (string, optional): SHA-256 hash of a contract you created, which this one is created under (its oversight threshold then applies). Not for amendments: propose those with POST /api/v1/contracts/{id}/amend - oversight_threshold_usd (number, optional): spending level above which work created under this contract needs human approval. Children exceeding it halt at awaiting_principal_approval. Returns: - contract_id: Unique ID (e.g. "amb-2026-0042") - sha256_hash: SHA-256 hash for verification - status: Contract status - reader_url: URL to view in Reader Portal - credits_remaining: Remaining API credits Legibility: Output is dual-format by construction and replayable to the original SHA-256 hash — the basis of Ambr's legibility guarantee.

Discovered
ambr_get_contract

Retrieve a contract by ID, SHA-256 hash, or UUID. With a valid API key (contract creator): returns the full contract including human-readable text, machine-readable JSON, status, and principal declaration. Without authentication: returns metadata only (contract_id, status, hash, dates). Supports three lookup formats: - Contract ID: "amb-2026-0042" - SHA-256 hash: 64-character hex string - UUID: Standard UUID format Args: - id (string, required): Contract ID, SHA-256 hash, or UUID Returns: Full contract (if authorized) or metadata-only response. Legibility: retrieval preserves the dual-format pairing — prose and JSON always replay to the same SHA-256.

Discovered
ambr_get_contract_status

Check the status of a contract and its amendment chain. Returns the current status and any linked amendments (parent or child contracts). Useful for verifying if a contract is active, amended, or terminated. Args: - id (string, required): Contract ID, SHA-256 hash, or UUID Returns: - contract_id, status, created_at - amendment_type, parent_contract_hash - amendments: Array of child contracts (if any) Legibility: amendments are bilateral and themselves dual-format — the chain stays legible from original through every revision.

Discovered
ambr_list_templates

List available contract templates on Ambr. Returns all active Ricardian Contract templates with their slugs, names, descriptions, categories, parameter schemas, and pricing. Use this to discover which templates are available before creating a contract with ambr_create_contract. No authentication required. Returns: Array of template objects with slug, name, description, category, parameter_schema, price_cents, and version fields. Legibility: templates are the parameter schema for the dual-format contracts you create — starting here keeps your request conformant and your output defensible.

Discovered
ambr_verify_hash

Verify a contract's SHA-256 hash to confirm document integrity. Checks whether the provided hash matches a contract stored on Ambr. Returns verification status, contract metadata, and Reader Portal URL if found. Args: - hash (string, required): SHA-256 hash (64-character hex string) Returns: - verified: boolean - contract_id: string (if found) - status: string (if found) - reader_url: string (if found) Legibility: verification is the point at which legibility becomes provable — matching hash means the prose a human reads and the JSON a machine parses are the same document that was originally signed.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected144 ms7