Check selected files with TypeScript

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

Adds substantial behavioral context beyond the readOnly/openWorld/destructive annotations: no model, emit, plugins, or project code execution; inferred null checking plus JS checking when no config is present; and it discloses that skipped files, incomplete context, and limits are reported. The closing caveat that "no diagnostics is not proof of runtime safety" is exactly the kind of nuance annotations cannot express.

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?

Four tight sentences, front-loaded with what is returned, then scope, then side-effect-free guarantees, then caveats. No filler; each sentence adds a constraint or capability an agent would otherwise have to guess.

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?

With no output schema, the description still explains what comes back (compiler diagnostics) and that skipped files, incomplete context, and limits are surfaced. Combined with annotations covering safety, nothing material is missing for correct invocation.

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 100%, so the baseline is 3, but the description adds real semantics for the project parameter by stating what happens when no config is supplied (inferred null checking with JS checking). The files parameter's semantics are left to the schema.

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?

Names a specific verb and resource ("Return TypeScript compiler diagnostics for selected JavaScript/TypeScript files") and scopes it ("reports selected files only", "uses the full local project's declarations"). This implicitly separates it from scan_project/analyze_file, but no sibling is named explicitly, so it falls just short of the top band.

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?

Usage is implied by the scoping language (selected files, full project context), but there is no explicit when-to-use vs. when-not, no mention of the sibling tools, and no stated prerequisites such as needing an installed compiler. Adequate but leaves routing to inference.

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