start_host_component

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

Without annotations, the description carries the burden. It discloses key behaviors: the component is started only if not already STARTED ('Skip if already in STARTED state'), and it returns request information for progress tracking. It also mentions fine-grained control without affecting other hosts. This provides adequate transparency for a mutation tool.

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 well-structured with headings ([Tool Role], [Core Functions], etc.) and front-loads key information. While it is somewhat verbose, each section provides necessary detail without redundancy. It could be slightly more concise, but it's effective.

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 simplicity of two string parameters, the presence of an output schema, and sibling context, the description covers all essential aspects: purpose, usage scenarios, core functions (with idempotency), parameter examples, and return value. It is complete for an agent to select and invoke correctly.

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?

The input schema has 0% description coverage, but the description includes an 'Args' section with examples for each parameter (e.g., host_name: 'hdp-node-01.example.com', component_name: 'DATANODE', 'NODEMANAGER'). These examples clarify the expected format and meaning, adding value beyond the schema.

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 explicitly states 'Starts a specific component on a specific host in the Ambari cluster', with clear verb and resource. It distinguishes from sibling tools like start_service and restart_host_component by noting it's a 'Dedicated tool for starting individual host-level components, enabling fine-grained control without affecting other hosts or the overall service.'

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 includes a 'Required Usage Scenarios' section listing three specific scenarios when to use this tool (e.g., 'when a specific host's component is STOPPED but the overall service is STARTED'). It does not explicitly state when not to use it, but the scenarios imply appropriate contexts, and sibling tools provide alternatives.

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