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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description need not repeat those. However, it adds no additional behavioral context—no mention of how it resolves types (e.g., via files or snapshot), any failure modes, or constraints like requiring a TypeScript project. It doesn't contradict annotations, but it also doesn't enrich them, so it falls short of adding value beyond the structured fields.

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 a single sentence with no wasted words, which is concise. However, given the tool's complexity (7 parameters, nested objects, output schema), this brevity is under-specification rather than efficient conciseness. It's front-loaded with the core purpose but lacks the structural guidance an agent needs.

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 has 7 parameters including complex nested objects (files, packages, tsconfig), an output schema, and multiple sibling tools. The description only states the output, not how to invoke it correctly—no explanation of the oneOf between files and snapshot, no guidance on required 'name', and no mention of how the output is structured. This is severely incomplete for a tool of this complexity.

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 coverage is 0% (no parameter descriptions in the schema), and the description offers no explanation of the 7 parameters (name, kind, path, files, snapshot, packages, tsconfig). It doesn't clarify what 'name' refers to (e.g., declaration name), how 'files' vs 'snapshot' are alternatives, or what 'kind' and 'path' mean. With zero compensation for missing schema documentation, this is a critical gap.

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 tool's purpose: returning TypeScript type facts and call/construct signatures for a single declaration. It uses a specific verb ('Return') and resource ('type facts and call/construct signatures'), which differentiates it from siblings like get_definition (likely returns location) or find_symbol (likely returns symbol references). However, it doesn't explicitly contrast with those siblings, so it's clear but not fully distinguished.

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 no guidance on when to use this tool versus alternatives. It doesn't mention conditions like 'when you need type details' or 'use find_symbol for locating symbols instead'. Given the rich set of sibling tools, this lack of routing leaves the agent to guess, which is a significant gap.

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