Read one Firestore document by path and return its fields as plain JSON, or return exists:false if the document is missing.
Read one Firestore document by path (collection/document[/subcollection/document]); returns its fields as plain JSON or exists:false.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | Document path, e.g. users/alice | |
| database | No | Firestore database id; default (default) |
Changes observed during successful MCP inspections.
v0.2.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It usefully discloses the return shape ('fields as plain JSON') and the not-found behavior ('exists:false' rather than an error), but says nothing about permissions/auth requirements, latency, or error modes for malformed paths.
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?
A single sentence that front-loads the verb and resource, then packs the path grammar and return contract into a parenthetical. No redundant or filler wording.
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 two-parameter read tool with no output schema, the description covers the path format and the shape of a successful versus missing-document result, which is what an agent needs to call it correctly. Auth expectations and failure behavior on invalid paths are the only notable omissions.
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. The description goes beyond the schema by spelling out the nested path grammar 'collection/document[/subcollection/document]', which the schema's flat example 'users/alice' does not convey. It does not address the optional 'database' parameter, but the schema documents that adequately.
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 and resource ('Read one Firestore document by path') and scopes it to a single document, which implicitly distinguishes it from firestore_query (multi-document) and firestore_set/firestore_delete. It does not name those siblings explicitly, so the differentiation is inferred rather than stated.
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 singular 'one ... document' implies the single-fetch use case versus the sibling firestore_query, but there is no explicit when-to-use or when-not-to-use guidance, and no mention of prerequisites. An agent can infer the routing but must do so from wording alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.