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

With no annotations, the description carries the burden and it delivers: it discloses returned data ('compressed sources plus token stats'), the default budget, incremental skip behavior via since_hash, and an ordering prerequisite. The only notable gap is that it never states whether the shrink is read-only or mutates workspace files, which is relevant for a tool named 'shrink'.

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?

Six dense sentences with no filler, ordered from purpose to return to parameter guidance to prerequisite. Every sentence earns its place and the most important information is front-loaded.

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 8 parameters, no output schema, and no annotations, it covers purpose, return shape, defaults, incremental hashing, and a prerequisite. It only lacks detail on the skeleton categories and a few auxiliary context parameters, which are not required for a first correct call.

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 only 38%, and the description compensates for the most important parameters: workspace-vs-files choice, default token budget, and since_hash skip semantics. It leaves auxiliary parameters (stderr, active_file, user_prompt) unexplained, but the core invocation decisions are covered.

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 opening sentence names a specific verb and resource ('Shrink workspace files into AST-valid skeletons') and lists the output categories, so an agent knows what the tool produces. It does not explicitly contrast itself with siblings such as hexum_expand, though 'before reading a repo' gives some positioning.

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?

'Use this before reading a repo' gives a clear trigger, and the workspace-vs-files preference with a server-visibility condition is actionable routing. There is also a conditional prerequisite to call hexum_skill first, but no explicit when-not-to-use guidance for the other siblings.

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