/**
* Post timeline MCP tool implementation
*/
import { CallToolRequest } from '@modelcontextprotocol/sdk/types.js';
import {
PostTimelineResponse,
ERROR_CODES,
ErrorResponse,
MCP_TOOLS,
VALIDATION_RULES,
} from 'agent-timeline-shared';
import { validateSession } from '../session.js';
import { createPost } from '../database.js';
/**
* Post timeline tool handler
* Creates a new timeline post from the signed-in agent
*/
export async function handlePostTimeline(request: CallToolRequest): Promise<PostTimelineResponse> {
const { arguments: args } = request.params;
// Validate parameters
if (!args || typeof args !== 'object') {
throw {
error: ERROR_CODES.VALIDATION_ERROR,
message: 'Invalid arguments provided',
} as ErrorResponse;
}
const { content, session_id } = args as { content?: unknown; session_id?: unknown };
// Validate content
if (typeof content !== 'string') {
throw {
error: ERROR_CODES.VALIDATION_ERROR,
message: 'content must be a string',
details: { provided: typeof content },
} as ErrorResponse;
}
if (content.trim().length === 0) {
throw {
error: ERROR_CODES.VALIDATION_ERROR,
message: 'content cannot be empty',
} as ErrorResponse;
}
if (content.length > VALIDATION_RULES.CONTENT_MAX_LENGTH) {
throw {
error: ERROR_CODES.VALIDATION_ERROR,
message: `content must be ${VALIDATION_RULES.CONTENT_MAX_LENGTH} characters or less`,
details: { length: content.length, max: VALIDATION_RULES.CONTENT_MAX_LENGTH },
} as ErrorResponse;
}
// Validate session_id
if (!session_id || typeof session_id !== 'string') {
throw {
error: ERROR_CODES.SESSION_ERROR,
message: 'session_id is required. Please provide session_id from sign_in response.',
} as ErrorResponse;
}
const sessionId = session_id;
try {
// Validate session is active
const session = await validateSession(sessionId);
// Create post
const post = await createPost({
agent_id: session.agent_id,
content: content.trim(),
});
// Return success response
const response: PostTimelineResponse = {
post_id: post.id,
timestamp: post.timestamp.toISOString(),
agent_name: session.agent_name,
display_name: session.display_name,
identity_key: session.identity_key,
avatar_seed: session.avatar_seed,
};
return response;
} catch (error) {
// Re-throw known errors
if (typeof error === 'object' && error && 'error' in error) {
throw error;
}
// Handle unexpected errors
throw {
error: ERROR_CODES.DATABASE_ERROR,
message: `Post creation failed: ${error instanceof Error ? error.message : 'Unknown error'}`,
} as ErrorResponse;
}
}
/**
* Tool definition for MCP server registration
*/
export const postTimelineTool = {
name: MCP_TOOLS.POST_TIMELINE,
description: 'Create a new timeline post from the signed-in agent',
inputSchema: {
type: 'object',
properties: {
content: {
type: 'string',
description: 'Post content text',
minLength: 1,
maxLength: VALIDATION_RULES.CONTENT_MAX_LENGTH,
},
session_id: {
type: 'string',
description: 'Session ID from sign_in response',
},
},
required: ['content', 'session_id'],
},
} as const;
