grok_agent_session_begin

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

With no annotations, the description carries the full burden, and it does disclose the operation's return payload and the presence of a 'budget guard'. It does not explain side effects, whether an existing session is replaced, error behavior, or persistence implications of beginning a session, leaving meaningful behavioral gaps.

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 compact and front-loaded with the protocol version and core action before listing parameters and returns. The 'Session Protocol v1.2' prefix adds minor noise, but every other clause earns its place.

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 an 8-parameter tool with no output schema and no annotations, the description is too sparse. It helps an agent make a default 'call first' invocation, but it does not explain how to use five optional parameters, what the returned plan mode means, or how to react to deny_tools, making the description incomplete for the tool's complexity.

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 only 13%, and the description mentions only intent, goal, and host_budget, leaving project_root, test_commands, correlation_id, max_tool_calls, and expected_artifacts unexplained. For those undocumented parameters, the description adds almost no semantic value beyond what the schema already provides.

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 identifies the operation as 'begin session' with a specific protocol resource, and the return fields ('mode, plan, budget, deny_tools, host_script, skill_ref') give it a distinct identity. It does not explicitly compare itself to sibling tools such as grok_agent_start or grok_agent_session_next, so it falls just short of full sibling differentiation.

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?

'Call first' gives explicit positional guidance within the session lifecycle, which is valuable and actionable. However, it does not state when to prefer this over grok_agent_start or grok_agent_session_tick, nor does it mention any exclusions or preconditions beyond being first.

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