heliograph_gaps

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

With no annotations, the description carries full behavioral burden. It reveals key behavior: returns intervals sorted longest first, attributes each gap to the line before it, and reports an error when timestamps are all identical. It also explains the diagnostic rationale. It stops short of explicitly stating read-only semantics or exact output shape, but covers the most important behavioral traits.

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?

Four sentences, each carrying distinct value: concise purpose statement, return behavior, usage timing with rationale, and edge-case failure mode. No filler or repetition. The most decision-relevant information is front-loaded.

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 no output schema and no annotations, the description covers the essential contract: what is returned, ordering, attribution, and error condition. It does not specify the exact structured return format, but for an analysis tool of this complexity the description is nearly complete. An agent can correctly decide when to call it and interpret its result.

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 the 3 parameters (name, estate, min_seconds) are already fully documented in the schema. The description adds semantic context around the log/timestamp concept but does not meaningfully extend parameter understanding beyond the schema. Baseline 3 applies.

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 opens with a precise verb+resource statement ('Where a run stalled. Returns the intervals in the log's timestamp column') and clearly distinguishes itself from log-reading by positioning itself as the pre-reading analysis: 'Do this before reading a long log.' This makes the tool's identity and scope immediately obvious and separate from siblings like heliograph_read_log.

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 gives explicit when-to-use guidance: 'Do this before reading a long log: a hang and slow progress are indistinguishable without it.' It also explains when the tool cannot answer the question (buffered capture with identical timestamps). It does not explicitly name alternative tools or state when not to use it, but the timing guidance is clear enough.

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