const agentDefinition = {
  id: "context-pruner",
  displayName: "Context Pruner",
  publisher: "codebuff",
  version: "0.0.2",
  model: "openai/gpt-5-mini",
  toolNames: [
    "set_messages"
  ],
  spawnableAgents: [],
  inputSchema: {
    params: {
      type: "object",
      required: [],
      properties: {
        maxContextLength: {
          type: "number"
        }
      }
    }
  },
  includeMessageHistory: true,
  outputMode: "last_message",
  spawnerPrompt: `Spawn this agent between steps to prune context, starting with old tool results and then old messages.`,
  systemPrompt: ``,
  instructionsPrompt: ``,
  stepPrompt: ``,
  handleSteps: function* ({ agentState, params }) {
    const messages = agentState.messageHistory, countTokensJson = (obj) => {
      return Math.ceil(JSON.stringify(obj).length / 3);
    }, maxMessageTokens = params?.maxContextLength ?? 200000;
    let currentMessages = [...messages];
    if (currentMessages.length > 0) {
      const lastMessage = currentMessages[currentMessages.length - 1];
      if (lastMessage.role === "assistant" && typeof lastMessage.content === "string") {
        if (lastMessage.content.includes("spawn_agent_inline") && lastMessage.content.includes("context-pruner"))
          currentMessages.pop();
      }
    }
    if (countTokensJson(currentMessages) < maxMessageTokens) {
      yield {
        toolName: "set_messages",
        input: {
          messages: currentMessages
        }
      };
      return;
    }
    let numKeptTerminalCommands = 0;
    const afterTerminalPass = [];
    for (let i = currentMessages.length - 1;i >= 0; i--) {
      const message = currentMessages[i];
      let processedContent = typeof message.content === "string" ? message.content : JSON.stringify(message.content);
      if (processedContent.includes("<tool>run_terminal_command</tool>"))
        if (numKeptTerminalCommands < 5) {
          numKeptTerminalCommands++;
          afterTerminalPass.unshift({ ...message, content: processedContent });
        } else {
          processedContent = processedContent.replace(/<tool_result>\s*<tool>run_terminal_command<\/tool>\s*<result>[\s\S]*?<\/result>\s*<\/tool_result>/g, "<tool_result><tool>run_terminal_command</tool><result>[Output omitted]</result></tool_result>");
          afterTerminalPass.unshift({ ...message, content: processedContent });
        }
      else
        afterTerminalPass.unshift({ ...message, content: processedContent });
    }
    if (countTokensJson(afterTerminalPass) < maxMessageTokens) {
      yield {
        toolName: "set_messages",
        input: {
          messages: afterTerminalPass
        }
      };
      return;
    }
    const afterToolResultsPass = afterTerminalPass.map((message) => {
      let processedContent = typeof message.content === "string" ? message.content : JSON.stringify(message.content);
      if (processedContent.includes("<tool_result>") && processedContent.length > 1000)
        processedContent = processedContent.replace(/<result>[\s\S]*?<\/result>/g, "<result>[Large tool result omitted]</result>");
      return { ...message, content: processedContent };
    });
    if (countTokensJson(afterToolResultsPass) < maxMessageTokens) {
      yield {
        toolName: "set_messages",
        input: {
          messages: afterToolResultsPass
        }
      };
      return;
    }
    const shortenedMessageTokenFactor = 0.5, replacementMessage = {
      role: "user",
      content: "<system>Previous message(s) omitted due to length</system>"
    }, requiredTokens = countTokensJson(afterToolResultsPass.filter((m) => m.keepDuringTruncation));
    let removedTokens = 0;
    const tokensToRemove = (maxMessageTokens - requiredTokens) * (1 - shortenedMessageTokenFactor), placeholder = "deleted", filteredMessages = [];
    for (const message of afterToolResultsPass) {
      if (removedTokens >= tokensToRemove || message.keepDuringTruncation) {
        filteredMessages.push(message);
        continue;
      }
      removedTokens += countTokensJson(message);
      if (filteredMessages.length === 0 || filteredMessages[filteredMessages.length - 1] !== placeholder) {
        filteredMessages.push(placeholder);
        removedTokens -= countTokensJson(replacementMessage);
      }
    }
    yield {
      toolName: "set_messages",
      input: {
        messages: filteredMessages.map((m) => m === placeholder ? replacementMessage : m)
      }
    };
  }
}