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

Annotations supply readOnlyHint=false, idempotentHint=true, destructiveHint=false, openWorldHint=true, so the safety profile is covered. The description still adds meaningful behavior: the build is added to the user's app library as a side effect, which is not inferable from annotations or 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?

Two sentences, front-loaded with the core action and scope, followed by a useful provenance pointer. No wasted words, no repetition of schema content.

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?

Complete enough for a four-param, no-output-schema tool: the action, side effect, and the source of releaseId are covered. It doesn't specify whether the device must be a specific platform or what happens on install failure, but those are minor for this context.

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 names all four parameters and their sources. The description only adds hints for releaseId sourcing (firebase_list_releases), which is marginal value above the schema's own description 'Release id from firebase_list_releases'.

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 compound verb+resource: download a Firebase build and install it on a connected device in one step. It clearly distinguishes itself from the sibling app_install by note that the build becomes part of the app library and later installs only need app_install.

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?

Explicitly routes the agent to firebase_list_releases for obtaining a releaseId, and clarifies 'the latest build' is the first entry it returns. This is actionable when-to-use guidance tied to the parameter source.

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