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

With no annotations, the description carries the full burden. It discloses what is returned: 'new seeds deposited and traces left since that point, plus which pieces were touched.' This is helpful behavioral context, but it doesn't cover critical traits like read-only nature (though implied), ordering, pagination behavior, or potential performance. The absence of annotations means this falls short of being fully transparent.

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?

Two efficient sentences: the first states what it does, the second gives usage guidance. The core operation is front-loaded, and every sentence earns its place with no waste.

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 tool's relative simplicity (2 params, no output schema), the description is largely complete: it explains what is returned and when to use it. However, with no output schema, a fuller account of return structure (e.g., grouping by category, ordering) would improve completeness.

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 100%, so the schema already fully documents both parameters (timestamp format and limit). The description adds no additional parameter semantics beyond what the schema provides. Baseline 3 is correct when schema does the heavy lifting.

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 states a specific verb and resource: 'Show what changed in the graph since a given timestamp.' It clearly distinguishes this from sibling tools like graph_stats (aggregate state) and active_frontier (current front). However, it doesn't explicitly name an alternative or contrast, so a 4 is appropriate – the purpose is clear but sibling differentiation is implicit.

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 gives clear when-to-use guidance: 'Use this to orient after a gap, or to see what other agents have been working on.' This is more than implied usage, providing two concrete scenarios. However, no when-not guidance or explicit alternatives are offered, so it falls short of a 5.

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