fact_history

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

With no annotations provided, the description carries the full burden and does disclose non-obvious behavior: it follows a chain, includes both successors and predecessors, and orders results by valid_from. It does not mention output format or error cases, but the read-only nature is strongly implied by 'Trace' and 'Shows'.

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 tight, front-loaded sentences: the first states the operation, scope, and ordering; the second gives the user-facing purpose. Every word earns its place, with no filler or repetition.

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 single-parameter read tool, the description explains what is returned and how it is ordered, which is the core of correct invocation. It omits edge-case behavior such as unknown or invalid memory_id and does not describe the exact response shape, but the operation is simple and no output schema exists.

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 baseline applies; memory_id is already described as 'ID of the memory whose history to trace.' The description adds context about what the history includes, but does not add syntax or format details for the parameter itself.

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 ('Trace') and a specific resource ('supersession chain of a memory'), and clarifies the exact contents: the point itself, successors, predecessors via superseded_by, and ordering by valid_from. This clearly distinguishes it from generic graph/query siblings like graph_traverse or get_related.

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 clearly signals the context for use: when you need to see how a memory/fact evolved through supersession over time. It does not explicitly name alternatives or exclusion conditions, but the scope language makes the appropriate use case evident.

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