Server has 5 tools with basic naming (verb_noun pattern) but critical gaps in descriptions, schemas, and error handling. GET_CONTACTS and SEARCH_CONTACTS lack input schemas entirely (schema score 0). ADD_CONTACT, UPDATE_CONTACT, DELETE_CONTACT have nested object schemas but descriptions are generic and under 200 chars. No output schemas documented. No error recovery guidance. No parameter validation beyond type checks. Descriptions do not explain WHEN to use each tool or what distinguishes similar operations (e.g., GET_CONTACTS vs SEARCH_CONTACTS). No pagination support despite potential for large result sets. Tool names are clear but lack context about destructive operations in descriptions.

• Add output schemas for all tools. Document what fields are returned (e.g., contact_id, firstname, lastname, email, phone, createdate) so LLMs can chain calls. Example: GET_CONTACTS should return {type: 'object', properties: {contacts: {type: 'array', items: {type: 'object', properties: {id, firstname, lastname, email, phone}}}}}.
• Expand GET_CONTACTS description to 100-150 chars explaining it retrieves ALL contacts without filtering, and recommend SEARCH_CONTACTS for targeted queries. Add pagination parameters (limit, offset) and document max result limit (e.g., 100 per page).
• Add destructiveHint: true annotation to DELETE_CONTACT and include warning in description: 'This operation is irreversible. The contact will be archived in HubSpot.'
• Refactor ADD_CONTACT and UPDATE_CONTACT to accept optional properties object instead of requiring all four fields. Allow partial updates: {contactId, properties: {firstname?, lastname?, email?, phone?}}.
• Add error recovery guidance. Example: 'If contact not found, call SEARCH_CONTACTS to verify the contact exists before updating.' Include actionable error messages in implementation (e.g., 'Contact ID 12345 not found. Try searching by email.').