# Azure Key Vault vs Pulumi ESC > Azure Key Vault scores 74.7 (BB) on agent readiness against Pulumi ESC's 71.1 (BB), and leads in 4 of 7 scored categories. Pulumi ESC leads on payments & pricing. Both do secrets store. Category scores, facts, verdicts and agent notes side by side. - Canonical: https://www.anchorterminal.com/compare/azure-key-vault-vs-pulumi-esc - Markdown: https://www.anchorterminal.com/compare/azure-key-vault-vs-pulumi-esc.md (~2,500 tokens) - Slim: https://www.anchorterminal.com/compare/azure-key-vault-vs-pulumi-esc.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts) - JSON: https://www.anchorterminal.com/compare/azure-key-vault-vs-pulumi-esc.json (this page as data, same URL with Accept: application/json) - Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt) - API: https://www.anchorterminal.com/api/v1/index.json - Updated: 2026-10-08 Azure Key Vault scores 74.7 (BB) on agent readiness against Pulumi ESC's 71.1 (BB), and leads in 4 of 7 scored categories. Pulumi ESC leads on payments & pricing. Both do secrets store. - Azure Key Vault: grade BB, 74.7/100, rank #60 of 722. Markdown https://www.anchorterminal.com/tools/azure-key-vault.md · JSON https://www.anchorterminal.com/api/v1/tools/azure-key-vault.json - Pulumi ESC: grade BB, 71.1/100, rank #120 of 722. Markdown https://www.anchorterminal.com/tools/pulumi-esc.md · JSON https://www.anchorterminal.com/api/v1/tools/pulumi-esc.json ## Which one, for what ### Azure Key Vault (BB) Good for: Agents and runtimes already on Azure, where a managed identity reads a secret with no stored credential. Ahead on: - Reliability, 87 against 60 - Security & auth, 86 against 79 - Transparency & trust, 77 against 65 Watch for: No managed rotation for secrets. Key Vault raises a near-expiry event 30 days ahead and the owner's Azure Function does the rotation ### Pulumi ESC (BB) Good for: Teams already on Pulumi, or anyone who wants one place that composes static secrets, other vaults and short-lived cloud credentials, and agents that need to start with no signup. Ahead on: - Payments & pricing, 55 against 20 Also in its favour: - Free to start without a card Watch for: Audit logs, custom roles, team tokens, approvals and customer-managed keys need Pro ($400 a month) or Enterprise ## Score by category | Category | Weight | Azure Key Vault | Pulumi ESC | Edge | | --- | --- | --- | --- | --- | | Reliability | 16% (20 this run) | 87 | 60 | Azure Key Vault +27 | | Performance | 10%, pending | pending | pending | not scored in this run | | Schema & documentation | 13% (16.2 this run) | 85 | 82 | Azure Key Vault +3 | | Agent ergonomics | 13% (16.2 this run) | 75 | 75 | even | | Security & auth | 14% (17.5 this run) | 86 | 79 | Azure Key Vault +7 | | Payments & pricing | 10% (12.5 this run) | 20 | 55 | Pulumi ESC +35 | | Task success | 10%, pending | pending | pending | not scored in this run | | Maintenance & community | 7% (8.8 this run) | 80 | 82 | Pulumi ESC +2 | | Transparency & trust | 7% (8.8 this run) | 77 | 65 | Azure Key Vault +12 | | Negative events | ≤15 | 0 | 0 | | | **Total** | | **74.7 · BB** | **71.1 · BB** | | ## Facts side by side | Fact | Azure Key Vault | Pulumi ESC | | --- | --- | --- | | Kind | HTTP API | HTTP API | | Vendor | Microsoft Corporation | Pulumi Corporation | | Hosted endpoint | `https://.vault.azure.net` | `https://api.pulumi.com` | | Transports | HTTP | HTTP | | Auth | OAuth | OAuth or key | | Pricing | Pay per use | Freemium | | x402 | no | no | | Licence | Proprietary service under Microsoft's Product Terms. The Azure SDK client libraries are MIT | Proprietary service under Pulumi's Terms & Conditions. The Pulumi CLI, the ESC evaluator and the ESC SDKs are Apache-2.0 | | Read-only variant documented | no | yes | | llms.txt | no | yes | | Last release | 2026-10-02 | 2026-10-07 | | Terms last updated | no date given | no date given | | Privacy policy last updated | 2026-09-01 | no date given | | Customer content may train models | yes | not found in the text | | Terms restrict automated access | yes | not found in the text | | Terms restrict benchmarking | yes | not found in the text | | Terms or service can change without notice | not found in the text | yes | | Arbitration or class-action waiver | not found in the text | not found in the text | | Popularity | 2.6M npm/wk, 9.5M PyPI/wk | 21k npm/wk, 54k PyPI/wk | ## Verdicts **Azure Key Vault.** Access runs on Microsoft Entra ID tokens and Azure roles that can be scoped to one secret, with soft delete, a 99.99 per cent SLA and a public OpenAPI contract. Secret rotation needs an Event Grid trigger and a function the owner writes, audit logging is off until enabled, and an Azure subscription needs a person and a payment card. **Pulumi ESC.** An agent can start without a signup, because the Pulumi CLI creates a free ephemeral account that includes ESC, and the REST API has a public OpenAPI document. Audit logs, custom roles and approvals need the Pro edition at $400 a month, and no API rate limit was found in the reviewed documentation. ## Before you call either ### Azure Key Vault 1. Request a token for the resource https://vault.azure.net and send it as a Bearer header. Every call must carry `api-version`, such as 2025-07-01, because there is no default 2. Ask for the Key Vault Secrets User role on the vault or the single secret. Key Vault Reader returns metadata only, not values 3. Cache secret values in memory. A vault allows 4,000 reads and 300 secret creations per 10 seconds, and a subscription five times that 4. On 429 wait 1, 2, 4, 8 then 16 seconds. Throttled requests do not count against the limit 5. Don't retry Set Secret blindly. Each successful call creates a new version of the secret ### Pulumi ESC 1. Use `pulumi env`, not `esc`. The standalone CLI stopped at v0.26.0 and gets no security fixes 2. Read one value with `pulumi env open // ` so the whole environment doesn't enter context 3. Run tools with `pulumi env run -- `, which filters secret values from the command's output unless -i is set 4. Set PULUMI_ACCESS_TOKEN for the SDKs. From 0.14.0 they no longer read the CLI login on disk 5. Send `Authorization: token ` and `Accept: application/vnd.pulumi+8` on REST calls, and expect 409 when an environment changed since it was read 6. Relay the claim link an agent account prints. The account goes read-only after 72 hours and locks after 30 days unclaimed ## Questions ### Which is better for AI agents, Azure Key Vault or Pulumi ESC? Azure Key Vault scores 74.7 (BB) on agent readiness against Pulumi ESC's 71.1 (BB), and leads in 4 of 7 scored categories. Pulumi ESC leads on payments & pricing. ### Do Azure Key Vault and Pulumi ESC need an API key? Azure Key Vault uses an OAuth sign-in. Pulumi ESC takes an API key or an OAuth sign-in. ### Can an agent call Azure Key Vault and Pulumi ESC without installing anything? Yes. Azure Key Vault has a hosted endpoint at https://.vault.azure.net and Pulumi ESC at https://api.pulumi.com. ## For agents - This comparison as JSON: https://www.anchorterminal.com/compare/azure-key-vault-vs-pulumi-esc.json, and with the fewest tokens: https://www.anchorterminal.com/compare/azure-key-vault-vs-pulumi-esc.min.md - Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "azure-key-vault", "b": "pulumi-esc"}`. From a terminal: `anchor compare azure-key-vault pulumi-esc` - Each listing in full: https://www.anchorterminal.com/api/v1/tools/azure-key-vault.json and https://www.anchorterminal.com/api/v1/tools/pulumi-esc.json ## Other comparisons with Azure Key Vault or Pulumi ESC - [1Password service accounts, SDKs and Environments MCP vs Azure Key Vault](https://www.anchorterminal.com/compare/1password-vs-azure-key-vault.md) - [1Password service accounts, SDKs and Environments MCP vs Pulumi ESC](https://www.anchorterminal.com/compare/1password-vs-pulumi-esc.md) - [Akeyless (SecretlessAI and MCP server) vs Azure Key Vault](https://www.anchorterminal.com/compare/akeyless-vs-azure-key-vault.md) - [Akeyless (SecretlessAI and MCP server) vs Pulumi ESC](https://www.anchorterminal.com/compare/akeyless-vs-pulumi-esc.md) - [AWS Secrets Manager vs Azure Key Vault](https://www.anchorterminal.com/compare/aws-secrets-manager-vs-azure-key-vault.md) - [AWS Secrets Manager vs Pulumi ESC](https://www.anchorterminal.com/compare/aws-secrets-manager-vs-pulumi-esc.md) - [Azure Key Vault vs Bitwarden Secrets Manager](https://www.anchorterminal.com/compare/azure-key-vault-vs-bitwarden-secrets-manager.md) - [Azure Key Vault vs Doppler](https://www.anchorterminal.com/compare/azure-key-vault-vs-doppler.md) - [Azure Key Vault vs Google Cloud Secret Manager](https://www.anchorterminal.com/compare/azure-key-vault-vs-google-secret-manager.md) - [Azure Key Vault vs HashiCorp Vault + Vault MCP Server](https://www.anchorterminal.com/compare/azure-key-vault-vs-hashicorp-vault.md) - [Azure Key Vault vs Infisical](https://www.anchorterminal.com/compare/azure-key-vault-vs-infisical.md) - [Azure Key Vault vs Keeper Secrets Manager](https://www.anchorterminal.com/compare/azure-key-vault-vs-keeper-secrets-manager.md) - [Azure Key Vault vs Phase](https://www.anchorterminal.com/compare/azure-key-vault-vs-phase.md) - [Bitwarden Secrets Manager vs Pulumi ESC](https://www.anchorterminal.com/compare/bitwarden-secrets-manager-vs-pulumi-esc.md) - [Doppler vs Pulumi ESC](https://www.anchorterminal.com/compare/doppler-vs-pulumi-esc.md) - [Google Cloud Secret Manager vs Pulumi ESC](https://www.anchorterminal.com/compare/google-secret-manager-vs-pulumi-esc.md) - [HashiCorp Vault + Vault MCP Server vs Pulumi ESC](https://www.anchorterminal.com/compare/hashicorp-vault-vs-pulumi-esc.md) - [Infisical vs Pulumi ESC](https://www.anchorterminal.com/compare/infisical-vs-pulumi-esc.md) - [Keeper Secrets Manager vs Pulumi ESC](https://www.anchorterminal.com/compare/keeper-secrets-manager-vs-pulumi-esc.md) - [Phase vs Pulumi ESC](https://www.anchorterminal.com/compare/phase-vs-pulumi-esc.md)