get_error_chain

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds behavioral context by listing the three relationship types (leads_to, preceded_by, confused_with), similar to how a date-range constraint adds value. It does not disclose any additional caveats, but annotations sufficiently cover the basics.

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 three sentences, front-loaded with the action verb 'Traverse' and immediately explains the output structure. Every sentence earns its place: purpose, output details, and when to use. No fluff or redundancy.

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 a read-only graph traversal tool with a single parameter, the description sufficiently explains what the tool returns (leads_to, preceded_by, confused_with) and when to use it. No output schema exists, but the description covers the return content. It could benefit from noting any pagination or limits, but for this simple tool, the context is complete enough.

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 provides 100% coverage for the single parameter error_id, so the schema already documents the parameter. The description does not add extra syntax or format details beyond what is in the schema. Baseline 3 is appropriate since the schema carries the burden.

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 uses a specific verb ('Traverse') and resource ('error transition graph'), clearly distinguishing it from siblings like lookup_error or get_error_detail by explaining the graph relationships (leads_to, preceded_by, confused_with). This makes the tool's unique purpose unmistakable.

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 explicitly states when to use the tool: 'Use this to diagnose cascading failures and predict what comes next.' It does not explicitly mention alternatives or exclusions, but the context is clear. A 4 is appropriate because it provides clear use case guidance without naming alternatives.

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