get_segment_historic

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description's 'Fetches data. Makes no changes' is redundant but confirming. The description adds valuable behavioral context by stating the segment ID type restriction and the timestamp format, which are not in annotations. No contradiction with annotations.

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 concise: four short lines including an emoji and endpoint. It is front-loaded with the core purpose ('Retrieve a Segment's Historic Definition'). Every line adds meaningful information without redundancy or fluff.

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 is read-only with no output schema, the description adequately explains the what (historic definition), when (at a timestamp), and constraints (segment ID type). It could be more complete by hinting at the return format, but the purpose and parameters are fully covered, making it effective for an AI agent.

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?

Input schema descriptions cover both parameters ('SegmentId' and 'UTC milliseconds from the epoch'), giving 100% coverage. The description adds extra value by showing the HTTP path pattern (reinforcing parameter names) and explicitly stating the SegmentId limitation (non-numeric). This exceeds the baseline 3 for high coverage.

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 clearly states the verb 'Retrieve' and the resource 'Segment's Historic Definition'. It also specifies the endpoint pattern and distinguishes this tool from the current segment retrieval (e.g., 'retrieve_a_segment' sibling) by noting that it retrieves a segment 'as it existed at a given point in time'. The constraint 'Only segments with non-numeric SegmentIds are supported' further clarifies scope.

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 implies when to use: when you need a historic snapshot of a segment at a specific timestamp. It also provides a clear usage constraint (non-numeric SegmentIds only). However, it does not explicitly name alternative tools (e.g., 'retrieve_a_segment' for current definition) or state when not to use it, which would elevate it to a 5.

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