Bitrix24 MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden for behavioral disclosure. It mentions 'optional filtering' but doesn't describe key behaviors like whether this is a read-only operation, what permissions are needed, how results are paginated or sorted, or what the output format looks like. For a listing tool with zero annotation coverage, this leaves significant gaps in understanding how the tool behaves.

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?

The description is extremely concise at just 5 words, front-loading the core purpose without any wasted words. Every element ('List contacts', 'optional filtering') directly contributes to understanding the tool's function.

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?

Given the lack of annotations and output schema, the description is insufficiently complete. It doesn't explain what the tool returns (e.g., contact fields, format), behavioral constraints, or how it differs from sibling contact tools. For a listing operation in a complex CRM system with many alternatives, more context is needed for effective tool selection.

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 description coverage is 100%, with both parameters ('limit' and 'filter') well-documented in the schema. The description adds minimal value beyond this by mentioning 'optional filtering' which aligns with the 'filter' parameter, but doesn't provide additional context about filter syntax, examples, or limitations. This meets the baseline of 3 when schema coverage is high.

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 'List contacts with optional filtering' clearly states the verb ('List') and resource ('contacts'), making the basic purpose understandable. However, it doesn't distinguish this tool from sibling tools like 'bitrix24_get_contact', 'bitrix24_get_contacts_with_user_names', or 'bitrix24_get_latest_contacts', leaving ambiguity about when to use this specific listing tool versus other contact-related tools.

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 provides no guidance on when to use this tool versus alternatives. With multiple sibling tools for accessing contacts (e.g., 'bitrix24_get_contact' for single contact, 'bitrix24_get_latest_contacts' for recent ones), the agent receives no explicit or implied direction about appropriate contexts, prerequisites, or comparisons.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.