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

With no annotations, the description carries the full burden, and it discloses genuinely useful behavior: a fixed cost of 4 credits charged only on a successful return, plus the implicit read-only filtering rule that already-listed directories are excluded. It omits auth requirements, rate limits, and result format, but the cost and billing disclosure is strong value that structured fields do not provide.

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 core purpose and selection criteria are front-loaded in the first sentence, with the include constraint and cost follow-ups. Three sentences are dense and each carries information, though the opening sentence is long and slightly overloaded.

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 2-parameter tool with no annotations and no output schema, the description is reasonably complete: it explains what is returned, the filtering logic, the optional include expansion, and the credit cost. The main gap is that, absent an output schema, it does not describe the shape of each returned entry beyond 'where to submit'.

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 both parameters (count, include) are already documented in the schema. The description reinforces the include enum by naming what launch and review entries mean, but adds no syntax or default detail beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting.

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 states a specific resource (directories to list the product on) and enumerates the selection criteria: free, open to the product, not already listed, ranked by AI citations, with submission locations. An agent understands exactly what comes back. It does not, however, name or contrast any sibling tool (e.g. keyword_research or app_add), so it stops short of a 5.

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?

Guidance is limited to the include parameter ('Review profiles and launch platforms only when asked for in include'), which tells the agent when to expand scope, but there is no explicit when-to-use-this-tool-vs-alternatives statement. Usage context is implied by the filtering criteria rather than stated.

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