retell_add_knowledge_base_sources

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

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It states the tool adds sources but doesn't disclose whether this is a mutating operation (implied), what permissions are required, how sources are processed (e.g., indexing time), rate limits, or error handling. For a tool that modifies data without annotation coverage, this is inadequate.

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 a single, efficient sentence that front-loads the core action and resource. It wastes no words, directly stating the tool's purpose without redundancy. Every element ('Add documentation sources', 'URLs or text', 'to a knowledge base') contributes essential information.

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 tool's complexity (adding sources to a knowledge base, which likely involves data processing and mutation), lack of annotations, and no output schema, the description is incomplete. It doesn't explain what happens after addition (e.g., success response, error cases, or how sources integrate with the knowledge base), leaving significant gaps for an AI agent to understand the tool's full behavior.

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%, so the schema fully documents both parameters (knowledge_base_id and sources array with nested properties). The description adds no additional parameter semantics beyond implying source types ('URLs or text'), which is already covered in the schema's enum and property descriptions. Baseline 3 is appropriate as the schema does the heavy lifting.

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 action ('Add') and target ('documentation sources to a knowledge base'), specifying what types of sources (URLs or text) can be added. It distinguishes from siblings like 'retell_create_knowledge_base' (creates the base itself) and 'retell_delete_knowledge_base_source' (removes sources), but doesn't explicitly mention these distinctions in the description text.

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. It doesn't mention prerequisites (e.g., needing an existing knowledge base ID), exclusions, or comparisons with sibling tools like 'retell_create_knowledge_base' (for initial setup) or 'retell_update_agent' (which might involve knowledge bases). Usage context is implied but not stated.

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