session_trace_start

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

No annotations are provided, so the description carries the full behavioral burden, and it discloses almost nothing: not what a trace records, whether it is per-session or global, what happens if one is already active, nor any overhead or permission implications. A single sentence cannot cover a stateful recording tool with no annotation support.

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?

One front-loaded sentence with no filler or redundancy. It is efficient, though its brevity is partly under-specification rather than pure conciseness.

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?

An output schema exists, so return values need not be explained, but with four parameters at 0% coverage and zero annotations the definition leaves too much undocumented for a stateful start-recording operation. The sibling set clearly suggests a trace lifecycle the description never acknowledges.

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 0%, so the four parameters (trace_id, session_id, capture_html_on_error, capture_screenshot_on_error) are documented only by name and default. The description adds no meaning for any of them, leaving the two capture_* flags and the optional trace_id entirely unexplained.

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?

"Start recording session action trace" gives a specific verb (start) and resource (session action trace), which reads clearly against siblings like session_trace_stop and session_trace_get. It stops short of explicitly differentiating when this should be used versus those siblings, so it lands at 4 rather than 5.

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 offers no when-to-use guidance, no prerequisites, and does not mention the natural alternatives (session_trace_stop/get/export) that surround it. An agent must infer everything about timing and sequencing 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.