Read console variables (global and user)

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

With no annotations provided, the description carries the full burden and does so: it declares read-only semantics, a platform limitation (no API enumerates variables on grandMA3 2.5.1), shadowing behavior ('a user variable shadows a global one') surfaced via resolvesTo, whose user owns user variables, and a minimum bridge version (0.31.0). These are non-obvious operational facts an agent could not get from the schema.

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?

Nearly every sentence carries information, but the opening sentence is a tangled, comma-spliced fragment ('The values and types ... of global and user variables, by name, and every $variable the macros reference ...') that is harder to parse than it needs to be. The density is justified; the structure and grammar are not.

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 read tool with no annotations and no output schema, the description covers return content (values, types, resolvesTo, macro lines), defaults, platform limits, and prerequisites well. It is slightly incomplete on failure behavior — e.g., what happens when a named variable does not exist — which matters for a name-based lookup on a system that cannot enumerate.

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 baseline is 3, but the description adds meaning beyond it: it explains what `scope: both` actually yields (resolvesTo indicating which namespace a $reference resolves to), the default-when-empty logic for `names`/`referenced`, and that `referenced` results include the macro lines that use each variable. That is genuine semantic value over the schema text.

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 names a specific verb and resource ('Read ... global and user variables') and even enumerates the returned data (values and types: integer, double, text), so an agent knows exactly what the tool does. It does not explicitly name a sibling (e.g., gma3_set_variable as the write counterpart), though the leading 'Read-only' implicitly separates it from mutation tools.

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?

It gives real usage context: the default resolution of `referenced` when no names are supplied, the fact that variables cannot be enumerated on 2.5.1 so named lookup is required, and the tie-in to `gma3_command` expansion outside quotes. What is missing is an explicit 'use this instead of X' comparison against gma3_set_variable or other variable/object readers.

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