chat_start_stream

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

With no annotations present, the description must fully disclose behavioral traits, but it only states 'Start an AI assistant streaming message.' It fails to describe idempotency, side effects, permission requirements, or the nature of the streaming session. This is a critical omission for a tool that initiates a stateful interaction.

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 but at the expense of completeness. It is a single phrase that does not earn its place because it lacks vital information. The structure is not front-loaded with key details; it reads more like a title than a description.

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 presence of sibling tools like chat_append_stream and chat_stop_stream, the description should explain how this tool initiates a stream, what the output schema provides, and how to use the stream lifecycle. The brief text is wholly inadequate for an agent to understand the tool's role and proper invocation.

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%, so each parameter is well-documented in the input schema. The description adds no additional meaning beyond the schema, so it meets the baseline of 3 without penalty or bonus.

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 verb 'Start' and the resource 'AI assistant streaming message', which distinguishes it from related siblings like chat_append_stream and chat_stop_stream that handle continuing or ending a stream. However, it does not explicitly contrast with these siblings, and 'streaming message' could be clearer, so it falls short of a perfect score.

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?

No guidance is provided on when to use this tool versus alternatives such as chat_post_message or chat_append_stream. The description does not mention prerequisites, context, or exclusions, leaving the agent to infer usage from the name alone.

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