lineage

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

With no annotations, the description discloses the return type ('list[dict]') and the error behavior ('or the standard error dict'). It also cautions against reconstructing ancestry from memory or filenames, highlighting the tool's authoritative role.

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 with four short sentences, each serving a distinct purpose. The 'Mistake to avoid' adds practical guidance without bloat.

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?

The tool is simple (one parameter) and the description covers purpose, usage, return value, and a warning. No output schema is shown, but the return description suffices.

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?

Program_id is only typed as a string in the schema with no description. The description references it in the return statement, implying it identifies the program, but does not elaborate on format or meaning beyond that.

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 'Read the recorded ancestry for one evaluated program,' clearly stating the action and target. It distinguishes from siblings like next_parent by focusing on recorded ancestry rather than traversal.

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?

It explicitly says 'Call this when explaining how a strong program was reached or when choosing which prior operators and changes deserve closer study,' giving concrete use cases. It does not, however, name alternative tools or state when not to use it.

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