Signal Detail

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

Annotations already establish that this is read-only, non-destructive, idempotent, and open-world. The description adds valuable behavioral context by disclosing the response composition: list fields plus `analysis` containing fit scores, valuation scenarios, evidence sources, and related fact IDs. This helps the agent understand what the operation returns without relying solely on the output schema.

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 two sentences with no filler. It front-loads the core operation, then adds only relevant details about the response and analysis contents. Every sentence earns its place.

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-only tool with an output schema and strong annotations, the description covers all necessary context: how to obtain the ID, how the output relates to the list tool, and what the additional analysis field contains. Nothing essential is missing for an agent to select and invoke this tool correctly.

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%, and the single `signal_id` parameter is already well documented with an example and instruction to get IDs from `signals`. The tool description largely repeats this, adding no new parameter semantics beyond what the schema already provides. A baseline score of 3 is appropriate given the schema handles the burden.

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 and resource: 'Get one signal by ID'. It clearly differentiates from the sibling list tool `signals` by stating it returns a single signal and additionally includes the `analysis` field. This makes the tool's purpose unambiguous and distinct.

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 provides clear context: it is used to fetch a single signal by ID, and IDs come from `signals`. Mentioning 'Same fields as the list, plus analysis' implies the tool is the right choice when full analysis details are needed. It stops short of explicitly stating when not to use it or naming alternatives beyond `signals`.

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