string_length

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

No annotations are provided, so the description carries the disclosure burden. It implies a pure, deterministic read, but never states how characters are counted (Unicode code points vs. grapheme clusters vs. bytes), how empty or multi-byte strings behave, or that nothing is mutated. Adequate for a trivial helper but not rich.

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?

A single front-loaded sentence with no filler; the operation is stated immediately and nothing is wasted.

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?

An output schema exists, so return-value explanation is not required, and the tool is simple. Still, the description leaves the 'string_char_count' ambiguity and the character-counting semantics unresolved.

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?

One parameter with 0% schema description coverage; the schema only exposes the name 'text' and type string. The description's phrase 'of a string' confirms the input is a string but adds no format, encoding, or length-limit detail.

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?

Specific verb ('Return') plus resource ('character count of a string') makes the operation unambiguous. However, it does nothing to distinguish itself from the near-identical sibling 'string_char_count', which an agent could easily mistake for this tool.

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 on when to use this versus alternatives, and no exclusions. The presence of a sibling named 'string_char_count' with apparently identical semantics makes this omission more than cosmetic — the agent has no stated basis for choosing between them.

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