P&ID: Parse Tag

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds genuine behavioral detail beyond that: on success it returns the standard's own description (e.g. 'Flow Indicating Controller'), on failure the first offending letter, and the prefix map is replaceable. This tells the agent what to expect from a call in both outcomes.

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?

Two dense sentences that are front-loaded around the grammar model, with the override nuance placed last. It is information-rich and largely waste-free, though the phrasing is compressed enough to read as slightly opaque on first pass.

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 an output schema present, return values need not be explained, and annotations cover safety, so the description's job is mainly to convey the parsing model, which it does well. Minor gaps remain around the 'kind' modes (auto/instrument/equipment) and no explicit routing to sibling tools, but overall the definition is sufficient 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?

Schema description coverage is 100%, so the schema already documents tag, kind, and equipment_prefixes with examples. The description reinforces the prefix-map override ('Q quench tower' style) and the letter-by-letter grammar, but adds little beyond the schema, so 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 states a specific verb (parse) and resource (P&ID tag) and outlines the exact ISA-5.1 grammar components it decodes, so the agent understands the operation precisely. It does not, however, name or contrast itself with pid-related siblings such as pid_instrument_index or pid_equipment_list, so it falls short of full sibling differentiation.

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?

The note that equipment prefixes are not standardised and the default map 'can be replaced per call' implies when to override the map, which is useful context. But there is no explicit statement of when to use this parser versus related index/list tools, nor any stated prerequisites or exclusions, leaving usage mostly inferred.

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