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

Annotations already establish read-only, idempotent, non-destructive behavior. The description goes further by disclosing the 30,000-character truncation threshold, the 1,048,576-character per-file cap, and that file overrides truncation - behavioral traits the annotations cannot convey.

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 content is valuable but packed into one sprawling, hard-to-parse sentence with nested clauses ('in full when they come to at most 30,000 characters, otherwise by name and length, with file to read one'). It is front-loaded on the return shape but would benefit from breaking into discrete statements.

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 carries the return-shape burden and does so reasonably: it explains status fields, version history contents, file listing format, and truncation. A read tool with annotations covering safety is adequately covered, though the truncation mechanics remain terse.

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 schema already documents all three parameters, making 3 the baseline. The description adds only modest value, clarifying that version defaults to newest and that file returns one file in full regardless of overall size.

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?

States a specific verb (read) and resource (lambda), then enumerates exactly what is returned: status, versions, and files. It is distinguishable from read_logs and list_files, though the enumeration is buried in a dense sentence.

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?

Gives real usage context: 'Read the history before changing what you did not write' tells the agent when to call this, and it names the sibling list_demos as the key source for demos. No explicit when-not cases, but the guidance is actionable.

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