Explore, filter and export without writing SQL

1How FilterMate works

FilterMate applies a subset filter to your vector layers. Nothing is deleted or copied: the filtered layer simply shows only the features that match, exactly as if you had typed a provider filter in the layer properties. FilterMate builds that filter for you, in the native language of the data source (PostGIS SQL, SpatiaLite SQL or a QGIS expression for files). Raster and point cloud layers are filtered too: they are clipped to a temporary file that replaces their source while the filter is on (see Rasters and LiDAR point clouds).

Every spatial filter follows the same three-part pattern:

Attribute-only filters also work: with no target layers and no predicate, FilterMate filters the source layer itself on the features you selected in the Exploring zone. Filters can be chained with AND, OR and AND NOT, undone, redone, saved as favorites, and exported to a new file or GeoPackage project.

2Installation

From the QGIS plugin repository (recommended)

1. In QGIS, open Plugins → Manage and Install Plugins…
2. Search for FilterMate in the All tab and click Install Plugin.
3. A FilterMate button appears in the plugin toolbar. Click it to open the panel.

Manual installation

Download the ZIP from GitHub Releases, then either use Install from ZIP in the plugin manager or unzip it into your profile's plugin folder:

Optional: PostgreSQL / PostGIS

FilterMate filters PostGIS layers server-side. This needs the psycopg2 Python package inside the QGIS Python environment:

pip install psycopg2-binary

On Windows, run it from the OSGeo4W Shell that ships with QGIS. Without it, PostgreSQL layers still work through the generic OGR backend, only slower.

3The panel at a glance

FilterMate is a dock panel. By default it opens on the right side of the QGIS window and can be moved, floated or resized like any other QGIS panel.

The panel is made of five areas, from top to bottom:

The two stacks are separated by a handle that you can drag; the panel remembers where you left it. At most one section is open in each stack. Opening AGENT folds EXPLORING and FILTERING; opening FILTERING brings EXPLORING back. AGENT is shown by default and can be hidden in the Configuration tab.

The screenshots of this section were taken before the AGENT section and the title bar badges: they show the favorites button beside the layer badge and no AGENT section.

The Exploring zone works on the current layer, shown in the first row of the Filtering tab. By default it follows the layer selected in the QGIS Layers panel (the auto current layer button, first in the Filtering rail). Turn that button off to pick the layer manually from the drop-down.

Three selection modes are available. Ticking one un-ticks the others, and the header of each box expands or collapses it.

Single selection

Pick one feature from a searchable drop-down. The second row is the display expression: FilterMate detects a sensible name field automatically (name, label, id…) but you can type any QGIS expression, for instance "code" || ' - ' || "name". The blue arrows step to the previous or next feature.

Multiple selection

Tick as many features as you need. The list loads at most 1000 rows (configurable) so that huge layers never freeze QGIS. When the list is truncated, typing in the filter box searches the whole layer, and Select All in the right-click menu loads everything.

Custom selection (expression)

Write a QGIS expression; every feature it matches becomes part of the reference geometry. This is the mode to use for "all features": an always-true expression such as 1 or TRUE takes the whole source layer.

The exploring rail

The vertical buttons to the left of the selection boxes, from top to bottom. Rasters and point clouds keep the same frame: Zoom and the preview first, their own map tools next, then the link, More and Reset.

Each layer remembers its own exploring settings in the project, so switching layers and coming back restores your selection.

Each row of the Filtering tab is switched on and off by the button in the rail on its left. A row that is switched off is ignored when you press Filter, which lets you keep a buffer or a predicate configured without using it.

Row by row

The eight predicates

Buffers

• Positive buffer, e.g. 50 m: "everything within 50 m of the selected road". Use Intersect as the predicate.
• Negative buffer, e.g. -20 m on a polygon: keeps only the features well inside it, away from the edges.
• Expression buffer: the distance is evaluated per source feature, so a regulatory distance can come from an attribute.
• Distances are always in metres. Layers in a geographic CRS (degrees) are reprojected on the fly.

Centroids

The two centroid checkboxes replace polygons by a representative point (a point guaranteed to be on the surface) during the test. With very detailed polygons this can make a cascade several times faster, at the cost of exactness on the borders. FilterMate keeps the spatial index usable in both cases.

6Tutorial: your first spatial filter

Goal: show only the buildings and hedges within 50 m of one road. The screenshots use a small BD TOPO extract (one commune, 373 buildings, 130 road sections) stored in a GeoPackage, but any project with a line layer and a polygon layer will do.

Each step below shows the whole QGIS window, so you can check the map canvas and the panel against your own screen. The map extent is the same from step 2 to step 6.

1. Choose the source layer. Load your layers and open FilterMate. In the Layers panel, click the road layer: it becomes the source layer (the auto current layer button is on by default) and the Exploring zone switches to it.

   

2. Pick the reference road. In the Exploring zone, tick Single selection and choose a road in the drop-down. The canvas selects it (yellow). If the drop-down shows identifiers rather than names, change the display field in the row below.

   

3. Choose the target layers. Open the Filtering tab. Switch on Layers to filter (second rail button) and tick batiment and haie in the list.

   

4. Choose the predicate. Switch on Geometric predicates and make sure Intersect is ticked.

   

5. Add a buffer. Switch on Buffer value and type 50. The buffer type row (Round, 5 segments) can stay as it is.

   

6. Run the filter. Press the Filter button (first button of the action bar). The map canvas is frozen for the duration of the task and redrawn once at the end.

   

What FilterMate generated for the GeoPackage buildings layer, as you can read it in Layer Properties → Source → Provider Feature Filter:

ROWID IN (SELECT id FROM "rtree_batiment_geom"
          WHERE minx <= 598540.4 AND maxx >= 598349.4
            AND miny <= 6265342.3 AND maxy >= 6265157.7)
AND ST_Intersects("geom",
      ST_Buffer(ST_MakeValid(ST_GeomFromText('LineString (…)', 2154)), 50.0))

The first clause queries the GeoPackage R-tree so that SQLite only evaluates the expensive predicate on candidate rows. That is what turns a 6-minute cascade on a 37-layer project into a 3-second one.

7Action bar, undo and history

Buttons are greyed out when they cannot apply: Undo before any filter, Redo when nothing was undone, Export while the Exporting tab is not configured.

A favorite stores a complete filter: source layer, selection, predicates, buffer and target layers. Re-applying it takes one click, which makes favorites the natural way to keep regulatory or recurring queries.

The favorites menu

• Add filter saves the filter currently applied. It is disabled when no filter is active.
• Saved favorites are listed in the Quick filtering section at the top: one click applies them.
• Manage favorites… opens the manager described below.
• Export… / Import… exchange favorites as JSON files between projects or colleagues.
• Global favorites lists the favorites shared across all your projects.
• Maintenance holds database statistics and cleanup tools.

The favorites manager

• General: rename the favorite, add a description and tags, see its source layer, provider and usage count. Visibility switches between This project and All projects (global).
• Expression: the exact filter expression, editable for advanced users.
• Remote: publishing to a shared git repository. FilterMate uses the QGIS authentication manager for credentials, so a team can maintain a common library of filters. This requires the optional QGIS Resource Sharing plugin.

Apply runs the favorite on the current project, Save Changes stores your edits, Delete removes it. Favorites are stored in FilterMate's own SQLite database in your QGIS profile and, for project-scoped ones, in the project file too.

The Exporting tab writes the currently visible features of the chosen layers to disk, filters included. As in the Filtering tab, each row is enabled by its rail button.

GeoPackage projects

When the output format is GeoPackage and several layers are exported together, FilterMate embeds a QGIS project in the file with the layer group hierarchy, styles and CRS preserved. Before writing, a recap dialog lists what will be exported and lets you keep or flatten the group structure. Opening the resulting .gpkg in QGIS restores the whole map.

10Configuration

The Configuration tab exposes FilterMate's settings as a tree. Double-click a value to edit it; drop-down values offer their allowed choices. Most changes apply live; the dock position needs the panel to be closed and reopened.

Search bar. The tab has a search bar. Type part of a setting's name and FilterMate opens its branch and selects it. Press Ctrl+F while the tab is open to reach the bar, and Escape to clear it.

The mouse wheel. A list or a number box answers the wheel only after you click it. Until then the wheel scrolls the panel, so a value, such as the feature used as the source of the next filter, never changes by accident.

The tree also holds performance thresholds (when to switch optimisations on), the expression cache size, export defaults and the Extensions section (favorites sharing, QFieldCloud). The complete file lives at config/config.json in the plugin folder; config/config.default.json next to it documents every key and can be copied back to reset everything.

FilterMate picks a backend per layer, based on its data provider, and shows it in the header badge. The backend decides where the spatial test runs: in the database whenever possible, in QGIS otherwise.

Measured on real projects with version 4.8.9 (timings from filtermate.log):

• The map canvas is frozen during a filter task and redrawn once, so the interface stays responsive.
• Click the backend badge to see the backends available for the current layer and force one when the automatic choice is not what you want.
• Every step above a few milliseconds is logged with a ⏱ prefix; compare two runs by grepping the log.

Remote sources

A layer whose data is read over the network follows the same paths as a local one: WFS, OGC API Features, ArcGIS Feature and Map Server, WMS / WMTS / XYZ, WCS, vector tiles, remote EPT and COPC point clouds, files read through /vsicurl/, and MSSQL, Oracle and HANA databases. Three rules hold: no network read on the main thread, every read is bounded, and no result is wrong or partial without saying so.

• Attribute filters. An expression is sent to the server in its own language (OGC Filter, CQL2 or SQL) only when it translates completely. Unsupported functions and unknown fields are refused without changing the layer. The server filter is prepared in the background and installed on the layer with its identity and style kept.
• Spatial filters. For a web service target, FilterMate reads only the features inside the extent of the source (a server bounding-box request), tests the exact predicate on the copy, and keeps the keys. The copy is capped at 20,000 features and 90 seconds by default (APP.OPTIONS.REMOTE_MATERIALIZATION). A result cut by the limit is reported as partial, never as complete. A key list sent to a service holds 500 keys at most, and a service with no stable key refuses it.
• Exploration. Value lists, feature lists, zooms and filtered extents of a layer that is slow to count run in cancellable background tasks.
• Rasters. A remote COG, WCS or PostgreSQL raster holds values: statistics and previews run in the background on a bounded capture, and a WCS used as a source or a target is copied to a GeoTIFF of the session cache, limited to the kept zone. WMS, WMTS, XYZ and ArcGIS MapServer layers are rendered images: you can select a colour on a bounded render, and they are never a filter target.
• Vector tiles are targets only. The filter is written into the filter expression of the renderer and of the labeling rules, and Undo restores them.
• Remote point clouds (EPT, COPC over http) are read through PDAL 2.4 or later with the useful extent only, never as a whole, so they need an explicit zone.

Where QGIS cannot report a protocol error safely (before 3.26, or before 3.36 under Python 3.12), a service read is refused with a message. The dock, Processing, the Python API, REST and MCP share these paths.

FilterMate registers a Processing provider with ten algorithms and four models. The simplest algorithm, filtermate:batch_filter, applies one filter expression to several vector layers in a single run; the cross filters of FilterMate 5 are described in section 13. Because it is a regular Processing algorithm it can be used in the graphical modeler, in batch mode, or from Python:

import processing
processing.run("filtermate:batch_filter", {
    "INPUT_LAYERS": ["batiment", "haie"],
    "EXPRESSION": "\"etat_de_l_objet\" = 'En service'",
})

Objects drawn from a vector layer

Draw objects on a raster with SAM from points or polygons (filtermate:segment_from_features, experimental) draws one object per feature of a guide layer, with no click: a point is a click on the object, a polygon gives its bounding box and a point inside it. The output is a polygon layer in the CRS of the raster, with the attributes of the feature, sam_score (the score SAM gives its mask) and, for a polygon, sam_iou (overlap of the footprint with the drawn object, from 0 to 1). It runs in the background, changes no layer of the project and can be a step of a model. It uses the SAM model that the raster pipette installs (section 13).

processing.run("filtermate:segment_from_features", {
    "RASTER": ortho, "FEATURES": footprints, "OUTPUT": "memory:"})

Measured on 40 BD TOPO buildings (50 to 2000 m²) on a 25 cm orthophoto, the median overlap with the footprint is 0.81 with the box and a point inside it, and 0.73 from points alone. The BD TOPO footprint is not the roof seen from above: a low sam_iou points at a building to look at, it does not prove a change. The polygons can then be the SEGMENTS parameter of Filter layers of any type by the pixels of a raster (filtermate:cross_filter_from_raster), which accepts a polygon layer in any CRS in place of the pixel values.

The principle stays the same: EXPLORING selects on the current layer, FILTERING relates that selection to the layers to filter with its geometric predicates and buffer. When the current layer is a raster or a point cloud, the vector groups of EXPLORING make room for the panel of that kind; the selection becomes a source geometry (selected pixels vectorized, or footprint of the kept points).

Raster

• Bands: one row per band with its colour role (R, G, B, NIR, read from the renderer or guessed), the active band and the bands the pipette compares; RGB, IRC and RGB + NIR shortcuts.
• Pipette on the map, with a tolerance: similar pixels of the whole raster (a colour on an orthophoto, a value, a class of a paletted raster), the clicked object only (a pool, a roof, a field) or similar objects (the objects like the clicked one, within chosen ratios of its area). The two object targets draw with SAM when it is installed, and by colour otherwise (below). Ctrl+click adds a pick; the map outlines the objects and the selection strip gives the kept share.
• Value range: drag the handles of the histogram, on one band or on every colour band at once; the quantity can be the value itself or, from a DTM, the slope (degrees or %), aspect, hillshade or roughness. The Select button (or the preview box) hides the other pixels on the map.
• A raster calculator expression, with an Insert menu for the band references and the spectral presets allowed by the roles: NDVI vegetation, NDVI bare soil, NDWI water, ExG vegetation.

Point cloud

• ASPRS and LiDAR HD classes with presets (ground, vegetation, buildings, above ground, water, without noise).
• Z (to the millimetre), intensity and return ranges; height above a DTM computed with PDAL.
• Conditions chained with AND / OR on any attribute, the classification included: Classification = 6 with a height above the DTM of at least 9 m keeps the tall roofs (story 10).
• "Apply to the other tiles of the dataset" for data delivered in tiles (LiDAR HD).
• On the rail: the Identify button picks a class, the value pipette writes a condition around the picked value of the chosen attribute (Ctrl+click adds an OR), and the zone tool draws a rectangle, polygon, freehand shape or circle that cuts the footprint of the source.
• The object detector of the rail selects the object under the click (the cluster of points of its class: a building, a tree) or, with a right click on the button, every object of the cloud like it: area within chosen ratios of the clicked objects and, with same shape (on by default), compactness within the same ratios, so a hedge of the area of a tree is not taken for a tree.

Objects drawn by SAM (5.1, experimental)

The two object targets of the pipette can use SAM 2.1 tiny, a segmentation model that runs on your computer, on the CPU. Clicked object draws the object under the click. Similar objects draws it, then every object like it in the visible map. The objects are plain polygons: the filter applied to the other layers needs no model, and a saved filter replays without one. Without SAM, both targets find objects by their colour, and the Engine list of the PIPETTE group switches between the two.

Installation, at the first use

FilterMate ships neither the model nor its runtime. Choose Clicked object or Similar objects on a raster: a message offers to install SAM, onnxruntime (about 100 MB) and the model (62 MB). Nothing is installed before you agree, and nothing at the start of QGIS. Once you confirm, pip installs onnxruntime in the background, as a QGIS task, into your QGIS profile; the Python of QGIS is not modified. The model then downloads from a pinned revision, and each file is checked against its SHA-256 before it replaces anything. The download can be canceled and uses the HTTP proxy of the QGIS options. Apart from these two downloads, nothing leaves your computer.

An Install SAM… button stays in the group. If pip fails, the reason is in the FilterMate log and the group shows the command to run by hand in a terminal (the OSGeo4W Shell on Windows). If the model files are damaged, Repair the model… replaces the bad ones.

Gestures

The first click of an area prepares it: about 3 s under QGIS for Windows, then about 0.1 s per gesture.

Similar objects: proposals to keep or reject

Similar objects first draws the clicked object. The patches of a similar colour in the visible map, 120 at most, are then proposed to SAM, which redraws each one in the background. An object is kept when its area, and its shape with same shape, are within the ratios of the group compared with the clicked one, and when it looks like it. The objects found are proposals, outlined in dashes and outside the selection: click one to keep it, right click to reject it, Enter (or Keep) keeps them all, Escape (or Reject) rejects them all. About half of the objects proposed are buildings: keep or reject them before filtering with them.

The objects are polygons in the CRS of the raster, stored with the filter like any other raster selection. Processing (the SEGMENTS parameter), the REST API and the MCP tools (segments in raster_selection) accept them too.

What it is good at, measured

Median overlap with reference outlines (IoU, 1 is a perfect match) on a 25 cm orthophoto, 2026-11-09:

SAM suits buildings and other well delimited objects. Parcels did not reach the improvement we required, since a cadastral limit is often invisible on the image, and trees were not validated: hedges tend to merge. Use the colour engine or a vector layer for them. Similar objects are a start, not a finished tool: on ten buildings never used to set them, the median precision (found objects that are buildings) is 0.36 and the recall 0.32. Keeping and rejecting proposals sorts the rest: from the third choice, the proposals that look like the rejected ones are taken away (median precision of those left 0.21 to 0.33, no building lost). Full figures and the method: docs/SEGMENTATION.md.

Watch

What happens to the targets

Watch

Nine combinations

The source (the current layer) and the targets can be of any kind. FILTERING keeps its form: layers to filter, combine operators (AND, OR, AND NOT, or a replacement when the combination is unchecked), geometric predicates, buffer and centroids. One setting is new: the minimum coverage (%) of polygons by the source geometry. Disjoint, already one of the eight predicates, keeps what lies outside the source geometry for every kind of target. Each cell links to a detailed use case with settings to reproduce.

A tenth source needs no layer: a fixed geometry (WKT or extent) given to the Python or REST API, or to the cross_filter_from_geometry algorithm. A target identical to the source is refused, as are layers without geometry.

Results on the map

These screenshots were taken in QGIS 4.2 on a small synthetic data set.

Undo, project files, export

Clipped rasters (VRT) and point clouds (COPC) keep the layer id, style and position. Undo, Redo and Unfilter put the original sources back; the project is always saved with the original source and the clips are replayed when it is opened. Export writes rasters as GeoTIFF / COG and point clouds as LAZ / LAS / COPC / GPKG / CSV, alone or with vector layers.

Options

Raster and point cloud support are on by default. In the Configuration tab, APP.OPTIONS.RASTER.enabled and APP.OPTIONS.POINT_CLOUD.enabled switch each kind off or on; the layer lists follow at once. Turning a kind off does not unfilter its layers: a warning names those that stay filtered. The APP.OPTIONS.CROSS_FILTER.* options set the point cloud clip mode (exact or bounding box), the maximum raster pixels, the footprint resolution, the cache size and the path of pdal.

Automation

Ten Processing algorithms (batch_filter and cross_filter from 4.x, cross_filter_from_raster, cross_filter_from_point_cloud, cross_filter_from_geometry, filter_point_cloud, clear_filters, apply_favorite, export_filtered_layers, segment_from_features) and four ready-made models (extraction by area, high vegetation near lines, parcels on gentle slopes, buildings missing from the LiDAR) run from the toolbox, qgis_process (the plugin starts without a QGIS window), Python and the REST API. See docs/AUTOMATION.md.

14Agent (5.1, experimental)

AGENT is a chat at the top of the panel. You write a sentence, for example buildings above 1200 m in the selected commune, and the agent filters, selects, zooms, shows or hides layers and exports. It uses the same filters as the rest of FilterMate. It is shown by default; the AGENT option of the Configuration tab hides it.

It can also find, describe and run Processing algorithms of QGIS (find_algorithms, describe_algorithm, run_algorithm, also through REST and both MCP servers), within limits: only the native and qgis providers, only an algorithm that makes a layer or only answers statistics, no SQL or Python executor, and inputs that are layers of the project, never a path or a URL. Each layer it makes is a temporary file added to the project, removed if you undo the turn, and Stop cancels the run.

Beyond filters, it can also:

• style and label a layer: one symbol, categories of a field, graduated classes, a raster colour ramp, an opacity, labels from a field;
• edit features: change values, add or delete features (you confirm a deletion). The layer is put in editing mode and nothing is written to its source until you save its edits, or discard them;
• make a print layout with a map, a title, a legend, a scale bar and a north arrow, to finish in the layout designer, and export it as PDF or PNG after you confirm;
• read and draw objects with SAM: use the objects drawn in the dock as a selection, draw objects from a layer of points or footprints, and look for objects like an example (about half of what it finds is right, and it finds about a fifth of what is there: the agent says so);
• keep notes for the project when you ask it to (which layer holds what, what you call things): up to 20, saved in the project and sent with each request.

Each of these is undone with the turn. A long conversation is summed up rather than sent again in full: past a certain length, the oldest requests are replaced by a few lines that say what they did.

Choose a model

• Free quota. The first time, the settings offer a few free requests a month, through a relay of FilterMate to Claude Haiku 5.5 (Anthropic), with no key to enter. The relay counts what is spent and keeps no conversation. Once the quota is used up, the panel asks for your own API key.
• Your own provider. Claude, Mistral, OpenAI, any OpenAI-compatible server, or a local Ollama model.
• The key is kept in the QGIS authentication database, which asks for its master password, never in a settings file. It is sent only to the server it was typed for, and you can remove it in the settings.
• Consent. Nothing leaves your computer before you have chosen a model and agreed. Changing the provider or its address asks again.

What you see

Requests, steps and changes appear as cards in the conversation. Each filter says how many features it kept, and warns when it kept none, with what to check. The conversation is kept per project on this computer and shown again when the project opens; the model does not get it back, so a conversation starts afresh. New conversation forgets what was kept for the project.

Filters apply at once, and each step can be undone

• While AGENT is open, Undo and Redo of the action bar (and Ctrl+Z, Ctrl+Y) walk the turns of the agent. Their tooltip names the request.
• The History page lists the turns, applied or undone, and sends a request again. For the last request it lists the steps: Undo back to here puts the layers as they were before the chosen step, as a step of its own that Undo takes back.
• Undo also reaches the layers a turn added or removed, the selections and the visibility. A removed layer comes back from its definition, with the same id and at its place in its group; a layer kept in memory cannot come back, and the panel says so. Zooms and exports are not undone.
• You can ask the agent to undo its last request. Stopping a request keeps what was done, and it can still be undone.

Confirmations and limits

• Exports and added or removed layers ask you first.
• A filter written by the model is one plain WHERE clause, read token by token against a list of what a filter needs: no subquery, no function outside the list. A selection by expression follows the same rule. A filter still reaches the database with your rights.
• A layer is added only from a plain data file, a public https address or a service listed by a source you ticked. The agent cannot give QGIS a provider string of its own, a PG: or a /vsi path.
• A bench of 39 requests in French and English, on a simulated project, scored 39/39 with Claude Haiku 5.5 on 2026-11-10.

Sources, ticked one by one

In the Sources tab of the settings, nothing is ticked at first. In the chat, only what is ticked can be used.

• Open data portals: data.gouv.fr, Opendatasoft, and the CKAN portals of the United Kingdom, Canada, Australia, Germany, Italy, the Netherlands, Ireland and Japan.
• WFS services: IGN, IBGE, PRG. A WFS layer must be listed by the service, and its address is built by the plugin.
• Sentinel-2 scenes from Earth Search, opened without downloading them.
• MCP connectors: remote servers such as the one of data.gouv.fr. Their tools join the conversation, and a tool that does not declare itself read-only asks you first. The plugin starts no process, so a server that only speaks stdio has to be run in HTTP mode.

Everything fetched from these servers is bounded: time and size are capped, and Stop works. A file on a server that gives parts of it (GeoPackage, GeoTIFF, zip) is read where it is. Any other file is copied to the filtermate/open_data folder of your QGIS profile first, within 512 MB and 3 minutes, without freezing the interface; an archive that would unpack to more than 2 GB is refused. Each failure says its cause: the status of the server, a web page, a file too large, too slow or cut, an archive with no layer.

What goes to the model

With each request, the provider you chose receives your sentence, the names of your layers and fields, the results of the tools it calls, and the state of the project:

• always: the project CRS, the scale, the visible extent and the active layer; up to 30 layers in the order of the layer tree, each with its kind, feature count, CRS when it is not the project's, group, visibility and filter; the selections;
• what changed since the last answer, when something did: layers added or removed, filters, visibility, selections, active layer, view, including what you changed outside the conversation;
• on request of the model, for one layer: its place in the tree, extent, style (renderer, field, number of classes, labels, opacity, scale range), joins and relations. Class values and labels are not sent.

Attribute values go to the model only if you allow them in the settings: without that, the tools that read values (field_values, layer_statistics, sample_features, identify_at) are not offered. Values already written in filters and favorites are still sent, and the dialog says so. With the free quota, the request goes through the relay to Claude Haiku 5.5.

MCP server built into the plugin

Off by default. In the agent settings, the Other applications tab turns it on: FilterMate then listens on http://127.0.0.1:17823/mcp (the port can be changed) and asks for an access token. Claude Code or another MCP client on this computer can drive FilterMate under the rules of the chat: the same tools, the same ticked sources, the same confirmations. Each change is a step of the panel's history and appears in the conversation with the name of the application. A change is refused while the chat is working or a QGIS dialog is open; reads go on.

• Buttons copy the configuration for MCP clients, the entry for Claude Desktop (which goes through mcp-remote, so it needs Node.js; it has not been tried with Claude Desktop itself) and the claude mcp add command. All three contain the token. New access token replaces it.
• The server listens on 127.0.0.1 only. With QGIS on Windows and the client in WSL 2, that address is not the same machine unless WSL uses mirrored networking.
• No Python package is needed. The stdio server described in docs/AUTOMATION.md stays available.

Developer notes: docs/AGENT_MODE.md.

15Troubleshooting

Where to look first

• QGIS Log Messages panel, FilterMate tab: warnings and errors of the current session.
• logs/filtermate.log in the plugin folder: the full log, including ⏱ timing lines. Set the environment variable FILTERMATE_LOG_LEVEL=DEBUG before starting QGIS for a verbose log.
• Switch FEEDBACK_LEVEL to verbose in the Configuration tab to see every message in the message bar.

Common questions

Getting help

• Report bugs with the log excerpt on GitHub Issues.
• Ask questions on the Discord server.
• Watch the video tutorials.