TOKYO – October 8, 2025 – Preferred Networks, Inc. (PFN) today released PLaMo™ 2.1 Prime, the latest version of PFN’s flagship Japan-made large-scale language model (LLM), which now incorporates automated tool calling functionality. This update enables PLaMo to automatically select tools that best fulfill the user’s instructions, where it can reference multiple internal and external databases, and integrate itself with external AI agents. PLaMo 2.1 Prime will be automatically updated from PLaMo 2.0 Prime, and existing users can continue using it without modification.

PLaMo’s Enhanced Agent Capabilities

1. Automated Tool Integration

PLaMo 2.1 users can now easily build advanced AI agents that can collaborate with multiple databases within and outside their organization. By automatically selecting and combining tools – such as web searches, internal database queries, external API calls, other AI agents – that best suit the user instructions, PLaMo generates comprehensive responses based on the collected information.

Example 1: Using PLaMo’s automated tool calling capability, the multi-AI agent queries the client management AI agent for client information and purchase history, and the inventory management AI agent for inventory status, then compiles this information to generate a comprehensive response.

Example 2: Using PLaMo’s automated tool calling capability, the AI agent extracts customers likely to be interested in Campaign B from an internal database, generates an email template for outreach, and automatically sends the email to the selected list of customers.

Other potential applications include:

• Creating an agent that searches a customer inquiry database to generate responses and sends alerts to employees when unable to produce an answer
• Integration with existing agents
  • Sending questions about company expenses to an accounting system AI agent for responses
  • Collaborating with a human resources management AI agent to automatically reference internal policies and inquiry databases

2. Improved Automatic Tool Selection and Calling Accuracy

While previous versions of PLaMo could already integrate with external systems when instructed to call specific tools, this update enables automatic selection and calling of the most appropriate tools for the user-specified conditions. Evaluations using the BFCL V3* benchmark for function calling performance demonstrate that PLaMo 2.1 Prime achieves a high level of accuracy.

Notes: 

• Berkeley Function Calling Leaderboard v3 (BFCL V3) is a benchmark consisting of approximately 2,000 question-tool-answer triplets that evaluates the ability to select appropriate tools in response to user instructions. “Simple” shows the ability to correctly call a single tool, while “Multiple” evaluates the ability to select and call tools from multiple options. “Live Multiple” evaluates this capability in more practical real-world scenarios by collecting data from unspecified users, assessing the ability to select optimal tools from multiple options in real-life conditions.
• GPT-5 does not perform tool calling but tends to rely on its own knowledge or attempt interactive dialogue, resulting in lower performance on the BFCL V3 benchmark. This may sometimes be desirable for certain use cases, such as conversational chat, and does not mean PLaMo 2.1 Prime outperforms in some scenarios.

PFN will continue its full-scale development of PLaMo, Japan’s high-performance Japanese-language large-scale language model, and strengthen feature development to expand PLaMo’s application cases.

About PLaMo™

PLaMo (pronounced “Plah-Mo”) is a brand for large language models (LLMs) developed in-house by PFN fully from scratch. Trained on high-quality datasets rich in Japanese content, PLaMo models have demonstrated world-class Japanese-language performance. Available models include the commercial flagship PLaMo Prime, lightweight PLaMo Lite for edge devices such as cars and manufacturing equipment, PLaMo-100B-Pretrained for non-commercial research purposes, PLaMo-fin-base additionally trained with Japanese financial knowledge, and PLaMo Translate specialized for Japanese text translation. PLaMo 1.0 Prime is offered through cloud APIs, Amazon Bedrock Marketplace, and on-premises, with built-in by default in external services such as miibo (Japanese AI building platform), Tachyon Generative AI (corporate AI service), and QommonsAI (used by over 150 local governments in Japan).