nylas_list_contactsList contacts for the connected account, with optional email/phone filters. Nylas v3: GET /v3/grants/{grant_id}/contacts.
| Name | Required | Description | Default |
|---|---|---|---|
| No | Filter by email address. | ||
| limit | No | Max contacts to return. | |
| grant_id | No | Connected-account grant id. Overrides NYLAS_GRANT_ID for this call. | |
| page_token | No | Pagination cursor (next_cursor from a prior page). | |
| phone_number | No | Filter by phone number. |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=true, so the tool is safe. The description adds the endpoint path and filter options but does not disclose pagination behavior or rate limits beyond what the schema provides.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences, front-loaded with purpose and key features, followed by technical reference. No wasted words.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a list tool with well-described schema and clear read-only annotation, the description is adequate. It does not explain pagination details but the schema covers page_token. Overall complete enough.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% with detailed parameter descriptions. The description summarizes email/phone filters but adds no new meaning beyond the schema, so baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool lists contacts for a connected account with optional filters, distinguishing it from single-contact retrieval (nylas_get_contact) and other list endpoints.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies usage for retrieving a list of contacts but lacks explicit guidance on when to use this tool versus alternatives like nylas_get_contact or other list tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct resource and action: create vs list vs get for specific entities like draft, event, calendar, contact, grant, message, folder. There is no overlap, as even similar verbs like 'list' are paired with unique nouns. Agents can easily select the correct tool.
All tool names follow a uniform 'nylas_verb_noun' pattern using snake_case, with clear and predictable verbs (create, get, list, send) and nouns (draft, event, calendar, etc.). The naming is fully consistent across all 15 tools.
With 15 tools, the set is well-scoped for a Nylas integration covering email, calendar, and contacts. Each tool serves a clear purpose without redundancy, and the count falls comfortably within the ideal range of 3-15 tools.
The tool set covers reading and limited creation (drafts, events) but lacks update and delete operations for all entities, as well as create for contacts. This leaves notable gaps for full lifecycle management, though core workflows like listing and fetching are present.