Graphql Schema Extend

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

With no annotations, the description carries the full load, and it does disclose genuinely useful behavior: the tool verifies the config object exists before writing, and that object is absent on most sites. But it never says how the extension is persisted (config write vs. code), whether it is reversible, or what happens on a failed verification — and the rest is a bug post-mortem rather than behavioral guidance.

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 purpose is front-loaded in one sentence, but the remaining prose is a changelog narrative about a previous call's drush config:set mistake. That history does not help an agent decide or invoke correctly and consumes most of the description.

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 values need not be explained, but for a two-parameter write tool with no annotations the description omits the parameter structure and the mutation's prerequisites/effects, leaving real gaps for correct invocation.

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 0% and both parameters are undocumented, including a nested free-form `fields` object with additionalProperties. The description only hints that `fields` holds "custom fields" and never explains what `type_name` should be or the expected shape of the fields object.

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 opening sentence gives a specific verb and resource ("Extend GraphQL schema with custom fields"), which separates it from siblings like graphql_schema_get and graphql_query. However, it never names those siblings or clarifies the boundary explicitly.

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 description implies a precondition (the site must have a graphql.schema.customization config object) and warns that most sites lack it, which is useful context for when this tool will work. It never states when to use this versus graphql_schema_get/graphql_query, nor does it describe alternatives.

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