The Cable Code

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

Annotations already declare readOnly, idempotent and openWorld=false, so the safety profile is covered. The description adds genuine extra context: it is deterministic (no LLM), and it discloses its standard coverage (~36 coding systems), which sets expectations about codes that may not decode. It does not say what happens on an unrecognized symbol, which keeps it short of a 5.

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?

Purpose and return shape are front-loaded in the opening clause, and the 'Deterministic, no LLM' qualifier is a tight, useful second sentence. The long enumeration of standards is somewhat dense but buys real coverage information, so the text largely earns its place.

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 usefully names the returned layers and states that each symbol carries its source, which is enough for an agent to consume the result. Gaps remain around the undocumented 'lang' parameter and error behavior for unrecognized codes, but the core contract is complete.

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 description coverage is only 50%: 'code' is well documented with realistic examples, but 'lang' has no description at all and the description never explains it (output language? input language?). With half the parameters undocumented in the schema, the description needed to compensate and does not mention either parameter.

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 (decode) and resource (cable type designation) and enumerates exactly what the decoding yields: conductor, insulation, screen, armour, sheath plus the source symbol. An agent knows precisely what the tool produces without opening any schema; there are no siblings to disambiguate from.

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?

Usage is implied by the subject matter (interpreting a cable code) and the note that it is deterministic with no LLM, which tells the agent to trust the result as a lookup rather than a generative guess. However there is no explicit when-to-use/when-not statement, no mention of what to do with an unparsable code, and no alternative tool is named.

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