grpcurl · FullStory
grpcurl for AI Agents
Discover and invoke gRPC services from scripts without generating a client.
Install for an Agent
Choose an official installation path that matches the runtime. Pin a version for team or CI use, then record the version before the first task.
Structured Output for Reliable Automation
Prefer a machine-readable format. Treat stdout as the result channel and stderr as diagnostics so the agent can parse failures separately.
R0–R3 Command Risk Guide
Risk is assigned per command. R0 is local or remote read-only, R1 is reversible local write, R2 changes remote state, and R3 can be irreversible or production-impacting.
Read-only does not mean public
R0 only means the command does not change local or remote state. A read-only command may still return secrets, identity data, configuration, or production data. Expose only the minimum needed for the task, and never place it in logs, prompts, or commits.
How the Agent Readiness Score Is Built
Readiness describes how reliably an agent can operate the tool. It does not make every command safe and it does not replace an independent execution test.
Documentation indicates an agent-readiness score of 84/100. No local execution test has been recorded.
Generate a Skill or Agent Policy
Choose an agent and safety mode to generate a copyable artifact with installation, allowed commands, approval boundaries, and the evidence limitation.
---
name: grpcurl-agent-workflow
description: Use grpcurl for gRPC reflection, service discovery, RPC testing with explicit command risk and evidence boundaries.
---
# grpcurl agent workflow
Use this skill when the task needs gRPC reflection, service discovery, RPC testing, JSON request bodies.
## Evidence boundary
- Registry confidence: `docs-verified`
- Documentation checked: `2026-07-10`
- Locally tested version: `not tested`
- Do not describe this CLI as locally verified until its commands have actually been executed in an isolated environment.
## Executed smoke checks
- No local execution record is available.
## Installation
- Homebrew (macos, linux): `brew install grpcurl`
- winget (windows): `winget install fullstorydev.grpcurl`
## Authentication
- Methods: none, metadata token, client certificate, TLS
- Secret environment variables: `GRPC_TOKEN`
- Minimum permissions: Use TLS and credentials scoped to the target service; begin with reflection and read RPCs.
- Credential storage: For headless runs, inject GRPC_TOKEN from the CI or platform secret manager at process start. For local interactive use, prefer the CLI or operating-system credential store when the official client supports one. Never save values in repository files.
- Never print, persist, or commit credential values.
## Allowed commands (read-only)
- `grpcurl -format json api.example.com:443 list` — R0: Uses server reflection to discover available services.
## Commands requiring explicit approval (read-only)
- None recorded.
## Forbidden commands (read-only)
- R2 `grpcurl -d @ api.example.com:443 package.Service/Method < request.json` — May change remote state depending on the method implementation.
## Execution rules
1. Mode boundary: R0 exact commands may be used; R1, R2, and R3 commands are forbidden.
2. Confirm the selected account, project, context, database, namespace, or environment before any command.
3. Prefer structured output using `-format json`, `-emit-defaults`.
4. Capture the exact command, exit code, stdout, and stderr separately.
5. A generated prefix policy must prompt unless that exact prefix is explicitly marked suffix-safe; do not infer safety from the executable name.
6. Never broaden credentials or disable safety controls to make a command succeed.
## Official sources
- [grpcurl documentation](https://github.com/fullstorydev/grpcurl#usage)
- [grpcurl documentation source repository](https://github.com/fullstorydev/grpcurl)
Verification History and Official Evidence
CLI Finder records documentation review separately from real execution. Installation, help, exit codes, and output cannot be called Verified until they were run.