Plunger
A lightweight native API testing tool written in Rust that provides unified observability for both human and AI agent operations. It proxies agent API calls through the MCP protocol, displays call details in real time, and includes built-in token-hiding and placeholder security mechanisms.
Timeline (last 90 days)
Plunger is a lightweight native API testing tool written in Rust, serving both the developer themselves and the AI Agent collaborating with the developer
Plunger is completely free and open source
Plunger can be installed via the command pip install plunger-cli
Plunger puts human operations and AI Agent operations under unified observation and management in the same interface, where users can manually send requests while AI Agents call APIs through MCP
Plunger exists as an MCP Server, proxying requests that Agents make to target APIs, capturing and displaying all call details
Plunger displays every API call made by the AI Agent in real time as a Live stream in the interface
Plunger hides real tokens by replacing actual keys with placeholders at the storage layer, so that request records do not write plaintext keys to disk
Plunger supports re-running any call made by the Agent via the CTRL-ENTER shortcut
All Facts (8)
Plunger is a lightweight native API testing tool written in Rust, serving both the developer themselves and the AI Agent collaborating with the developer
50%UnverifiedPlunger is completely free and open source
50%UnverifiedPlunger can be installed via the command pip install plunger-cli
50%UnverifiedPlunger puts human operations and AI Agent operations under unified observation and management in the same interface, where users can manually send requests while AI Agents call APIs through MCP
50%UnverifiedPlunger exists as an MCP Server, proxying requests that Agents make to target APIs, capturing and displaying all call details
50%UnverifiedPlunger displays every API call made by the AI Agent in real time as a Live stream in the interface
50%UnverifiedPlunger hides real tokens by replacing actual keys with placeholders at the storage layer, so that request records do not write plaintext keys to disk
50%UnverifiedPlunger supports re-running any call made by the Agent via the CTRL-ENTER shortcut
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