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

With no annotations, the description carries full responsibility for behavioral disclosure. It offers cryptic phrases like 'DECODE_OK or no file' and 'Never expand' without explaining what they mean. It does not disclose return values, side effects, or safety implications, making it nearly useless for an agent to predict 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 extremely short, but conciseness is not the same as clarity. The phrase 'PCCX squeeze' is front-loaded but is cryptic and unhelpful. The structure is a series of fragments with no logical flow, making it poorly organized despite its brevity.

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 tool with two optional parameters and no output schema, the description fails to explain how the parameters relate (source vs data_b64), what the tool returns, or any examples of use. It is entirely inadequate for an agent 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?

The input schema has 100% description coverage for both parameters ('source' and 'data_b64'), so the schema already documents their meaning. The description adds no additional parameter semantics, but since the schema is comprehensive, the baseline of 3 applies.

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 says 'PCCX squeeze' which largely repeats the tool name and provides no clear statement of what the tool does. It mentions 'POST /v1/squeeze' indicating an HTTP endpoint, but the actual purpose (e.g., compressing/encoding data) is never explicitly stated. This is barely above a tautology.

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?

No guidance is given on when to use this tool versus alternatives. The description does not mention any context, prerequisites, or exclusions, leaving the agent entirely without direction on selecting this tool among the many siblings.

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