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

With no annotations, the description carries the full burden, and it does well: it discloses the return shape (data plus confidence score and review_needed flag) and the credit cost per successful call. It does not mention error cases or rate limits, but those are not central to this tool's behavior.

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 four sentences, front-loaded with the core purpose, and every sentence adds value: use case, argument passing, sibling alternative, optional parameters, output, and cost. No filler or repetition of schema fields.

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 no annotations and no output schema, the description covers the crucial return information and cost. It also explains the primary alternative, which is important for tool selection. It leaves out edge cases like schema validation failure, but overall the agent has enough to call it 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 coverage is 100%, so the baseline is 3. The description adds modest conceptual framing ('schema constrains the output shape', 'instructions guides extraction') but mostly paraphrases the schema property descriptions. No parameter semantics beyond the schema are provided.

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 first sentence states a specific verb and resource: 'Extract clean, schema-guaranteed JSON from raw/messy text you already have.' It also lists concrete input types and explicitly distinguishes itself from parse_document ('Use this instead of parse_document when you don't have a file'), so an agent can tell them apart.

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 gives a direct routing rule: use this over parse_document when there is no file. It also explains optional schema/schema_id/instructions usage in context, giving the agent enough to know when each control is relevant. It does not cover every sibling, but the named alternative is the key one.

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