install_php_extension

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

No annotations are provided, so the description must carry the full behavioral burden. It only restates the tool name and does not disclose side effects, required permissions, whether a PHP service restart is needed, reversibility, or any other behavioral trait beyond the implied mutation.

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 description is a single short sentence, so it is not verbose, but it is under-specified rather than appropriately concise. For a two-parameter mutation tool, this one-liner omits necessary context and fails to earn its place by providing useful information.

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?

Given no annotations, no output schema, 0% parameter description coverage, and two required parameters, the description is completely inadequate. An agent lacks the information needed to call the tool correctly or understand its effects.

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% for both required parameters, and the description adds no meaning. It does not clarify what 'id' refers to (e.g., a PHP runtime ID or host ID) or what format the 'extension' string should take, leaving both parameters fully undocumented.

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 ('Install') and resource ('PHP extension'), so an agent can immediately tell it is a mutation tool for PHP extensions. However, it does not differentiate from siblings like uninstall_php_extension or list_php_extensions, leaving that distinction to the name alone.

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?

There is no guidance on when to use this tool versus alternatives. It does not say to check list_php_extensions first, nor does it mention prerequisites such as a valid PHP runtime ID or whether the extension must already be available. No when/when-not context is provided.

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